EXTREME SOUTHWESTERN CALIFORNIA AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN DIEGO CA 200 PM PDT SUN MAY 9 1999 A DEEP MARINE LAYER AND ONSHORE FLOW WILL CONTINUE THE LOW CLOUDS WITH LOCAL FOG WEST OF THE MOUNTAINS TONIGHT. HIGH PRESSURE BUILDING OFF THE COAST WILL BRING EARLIER CLEARING AND WARMING MONDAY AND TUESDAY. THE MOUNTAINS AND DESERTS WILL REMAIN CLEAR THROUGH TUESDAY. GUSTY NORTHWEST WIND IN THE MOUNTAINS WILL DIMINISH TONIGHT AND MONDAY. VISIBLE SATELLITE LOOP AND METAR REPORTS INDICATE CLEARING IS TAKING PLACE OVER SOUTHWEST SAN DIEGO COUNTY...PORTIONS OF THE INLAND EMPIRE AND OVER THE COASTAL WATERS. AT 20Z THE COASTAL EDDY WAS ABOUT 45 NM SOUTH OF SAN CLEMENTE ISLAND...ACROSS THE BORDER INTO MEXICO...AND CONTINUING TO DRIFT TO THE SOUTHWEST ABOUT 15 KNOTS AND AWAY FROM THE COAST. AS THE EDDY DRIFTS SOUTHWEST IT IS PULLING THE LOW CLOUDS SOUTHWEST AS WELL RESULTING IN THE CLEARING TAKING PLACE OVER THE SAN DIEGO AREA. INLAND EMPIRE CLEARING APPEARS TO BE THE RESULT OF DRAINAGE OFF THE SURROUNDING MOUNTAINS. BOTH THE 03Z MESO ETA AND THE 15Z RUC MODEL SUGGEST THE EDDY WILL BE GONE BY THIS EVENING. HOWEVER...STRONG GUSTY NORTHWEST WIND NEAR POINT CONCEPTION IS STILL SUFFICIENT TO MAINTAIN AND EDDY OFFSHORE SO EXPECT SOME EDDY CIRCULATION THROUGH THE NIGHT. RECENT ACARS SOUNDINGS OVER SAN AND LAX INDICATE THE BASE OF THE MARINE INVERSION WAS ABOUT 4000 FEET...SLIGHTLY LOWER THAN THE 4500 FEET INDICATED ON THE NKX 12Z SOUNDING...BUT STILL DEEP ENOUGH TO KEEP CLOUDS OVER MOST OF THE INLAND AREAS THROUGH TONIGHT. 12Z MODELS IN AGREEMENT BUILDING A RIDGE OFFSHORE THROUGH MONDAY THEN MOVING THE RIDGE CLOSER TO THE COAST ON TUESDAY. FLOW REMAINS ONSHORE ALONG OUR COAST THROUGH THE PERIOD BUT THE GRADIENTS RELAX SO THE ONSHORE FLOW IS NOT EXPECTED TO BE AS STRONG. AVN MOS IS NOT AS HIGH WITH MAXIMUM TEMPERATURES FOR MONDAY AS THE NGM MOS IS...WHICH LOOKS REASONABLE WITH THE MARINE LAYER IN PLACE ...BUT THE REVERSE IS TRUE FOR TUESDAY. WILL LEAN TOWARDS THE AVN MOS BOTH DAYS EXCEPT FOR THE SAN DIEGO AREA ON TUESDAY WHERE THE NGM MOS APPEARS TO BE MORE REASONABLE GIVEN THE BELOW NORMAL WATER TEMPERATURES OFFSHORE. THE MRF SUGGEST AN OMEGA BLOCK MAYBE SETTING UP OVER THE GULF OF ALASKA ALONG 140W BY FRIDAY WITH AN ANCHOR LOW OVER THE PACIFIC NORTHWEST AND ANOTHER SOUTH OF THE ALEUTIANS NEAR 40N/170W. THE BLOCK THE MRF INDICATES DOES NOT LAST LONG AS THE PACIFIC NORTHWEST LOW RETROGRADES TO OFF THE OREGON COAST BY 240 HOURS. THE CANADIAN MODEL ALSO SUGGESTS A BLOCKING PATTERN BUT IT INDICATES A REX BLOCK AT 120 HOURS WITH A HIGH CENTER OVER THE NORTHWEST TERRITORIES OF CANADA AND THE ARCTIC OCEAN WITH THE LOW OVER BRITISH COLUMBIA. SAN 0000 .SAN...NONE. HORTON
FXUS66 KHNX 091631 ca INTERIOR CENTRAL CALIFORNIA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA 900 PM PDT SAT MAY 8 1999 SFO-LAS P-GRAD REMAINS NEAR 15MB THIS EVE...HOWEVER WINDS ARE BEGINNING TO DIMINISH AS SURFACE INVERSION STRENGTHENS AND LOWER LEVELS DECOUPLE. ALTHOUGH 00Z RUC INDICATES LITTLE CHANGE IN GRAD OVERNIGHT...FURTHER STABILIZATION IN LOWER ATMOS SHOULD KEEP WINDS BELOW GUSTY LEVELS EXPERIENCED EARLIER THIS EVE. WEAK CAA ON DRY NW FLOW HAS PROVIDED ADDITIONAL COOLING THROUGHOUT LOW-MID LEVELS AND SURFACE TEMPS ARE RUNNING A FEW DEGREES BELOW YESTERDAY AT THIS TIME. DESPITE SLIGHTLY LOWERED DEW POINTS...WEAK MIXING IN BOUNDARY LAYER OVERNIGHT SHOULD KEEP MIN TEMPS CLOSE TO CURRENT FORECAST PROJECTIONS. WILL PREPARE MINOR UPDATE TO ADJUST WIND SPEEDS DOWNWARD SLIGHTLY AROSS SJ VALLEY AND DESERT ZONES. HOWEVER NO OTHER CHANGES ARE ANTICIPATED AT THIS TIME. ALL POPS ZERO. .HNX...NONE. NESMITH
FXUS66 KEKA 090344 ca AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 915 AM EST SUN MAY 9 1999 WHILE MORNING SOUNDINGS /DTX AND ILN/ SHOW DECENT MOISTURE AROUND 850MB WITH STRONG INVERSION ABOVE THAT...DRIER AIR ADVECTING IN AND SUBSIDENCE SHOULD PRECLUDE WIDESPREAD CU DEVELOPMENT THIS AFTERNOON. CU FORECASTING SCHEMES SHOW BKN CU POSSIBLE THIS MORNING BUT CLR-SCT THIS AFTERNOON. 09Z RUC SHOWS ALL LOWER AND MIDDLE LEVELS DRYING OUT CONSIDERABLY THIS AFTERNOON. WILL LIKELY UPDATE IND ZFP TO MOSTLY SUNNY. WITH MORE SUN THAN PREVIOUSLY EXPECTED...MAY BUMP IND ZONES TO AROUND 70 FOR THIS AFTERNOONS HIGH. .IWX...NONE. REAUGH
FXUS73 KIND 090742 in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 732 AM CDT SUN MAY 9 1999 ISOLD SHWRS/TSTMS HAVE DVLPD FARTHER N UP MO RVR NR KOMA...KSDA AND KRDK. PCPN FORMED IN MID LVL ISENT LIFT WHICH IS DEPICTED IN 09Z RUC 800MB THETA-E CNVGNC ZN. 12Z KOAX SOUNDING INDCS CAPE ARND 1200 J/KG LIFTED FM 820MB. RADAR SHOWS VERY SLOW EWD MOVMT SO WL ADD MENTION OF ISOLD SHWRS/TSTMS TO EXTRM SWRN FA. SINCE PCPN IS SO ELEVATED DO NOT THINK IT WL DSIPT TOO MUCH ONCE LOW LVL JET WEAKENS THIS MRNG...BUT RUC KEEPS CNVGNC ZN AND QPF W OF FA THRU 21Z SO WL NOT EXPAND ANY FURTHER E FOR NOW. .DSM...NONE SMALL
FXUS63 KDMX 090827 ia AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TOPEKA KS 310 PM CDT SUN MAY 9 1999 ...SEVERE CHCS AND QPF ARE MAIN CONCERNS THIS FORECAST... BEST BET TNGT IS FOR SEVERE STORMS TO DEVELOP IN THE WEST ALG DRYER AIR... WITH ADDED IMPETUS OF UPPER WAVE MOVING IN FROM THE SRN ROCKIES PER SAT PIX...LATEST RUCII AND PROFILERS. BETTER LOW LVL DYNAMICS TMRW ALTHOUGH FEATURES ALOFT VERY WEAK. AS MENTIONED BY HPC...ANY MINOR WAVE IN SUCH A MOIST AND UNSTABLE ATMOS. COULD TRIGGER STORMS. AVM PREFERRED ALTHOUGH FOR THE BIG PICTURE...ALTHOUGH IT IS, OF COURSE, DOING POORLY WITH LESSER AMPLITUDE FEATURES. AVM FCST PRECIPITABLE WATER VALUES AROUND 150% OF NORMAL BY TMRW. SOME HEAVY RAIN PER HPC NOT OUT OF THE QUESTION BY TUESDAY SR. WITH TUESDAY AT LEAST TWO OUTFLOW BOUNDARIES AWAY...DIFFICULT TO SAY WHAT POPS WILL BE. HOWEVER...WITH REAL FRONT IN THE AREA...CAN NOT DISCOUNT A CONTINUED CHC FOR RAIN/THUNDER. WITH INCREASING PRECIPITABLE WATER VALUES/MIXING RATIOS...WOULD SUSPECT NEXT SEVERAL DAYS SOMEWHAT COOLER THAN TODAY..JUST A TAD ABOVE FWC MOS VALUES. DO THINK AVM POPS CLOSER TO WHAT IS EXPECTED. .TOP...NONE
FXUS63 KDDC 092000 ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PADUCAH KY 242 AM CDT SUN MAY 09 1999 LAST IN A SERIES OF SHORTWAVES SEEN ON WATER VAPOR APPROACHING THE MISSISSIPPI VALLEY THIS MORNING INITIALIZED WELL ON 00Z MODELS. THIS WILL BE CONCERN ONE...WITH NEXT CONCERN BEING THE INCREASING FLOW OF GULF MOISTURE AND PRECIP CHANCES THRU THE MID PART OF THE WEEK. SATELLITE SHOWING SOME LOW CLOUD FORMATION OVER SOUTH CENTRAL MO ATTM. SFC MAP INDICATES WEAK FRONTAL BOUNDARY VCNTY HRO-DYR-BNA. MODEL CROSS SECTIONS INDICATE LIMITED MOISTURE WITH S/W...BUT QPF VALUES POINT OUT WHERE DIFFERENCES EXIST. NGM AND RUC SUGGEST SMALL QPF VALUES IN A SWATH FROM S MISSOURI INTO MID TENN TODAY WHILE ETA HAS NONE AND MESOETA CRANKS OUT .01 IN MID TENN. IF NGM/RUC ARE CORRECT WOULD CERTAINLY NEED MORE CLOUDS AND PERHAPS MENTION OF MORNING SPRINKLES IN SEMO/FAR W KY ZONES TODAY...WHERE CURRENT FORECAST IS MSLY SUNNY. THINK NGM MAY BE SOMEWHAT OVERDONE BUT WILL TAKE A MIDDLE GROUND PATH BETWEEN IT AND DRY ETA. WILL NOT MENTION PRECIP IN MORNING ZONES BUT MAY HOLD OFF ON FINAL SKY WORDING UNTIL VIEWING A FEW MORE SAT IMAGES PRIOR TO PRESS TIME. ACROSS NORTHERN TIER OF ZONES SHOULD BE LESS DIURNAL CU THAN PAST 2 DAYS...SO MOSTLY SUNNY FORECAST LOOKS OK. S/W SCHEDULED TO BE EAST OF FA BY 18Z OR SO...THEN WEAK RIDGE BEGINS BUILDING. GULF OPENS MONDAY AND BEYOND AS LOW LEVEL WIND FLOW VEERS DUE TO RETREATING HIGH AND DEVELOPING LEE SIDE LOW AND LLJ. AS USUAL THE MOISTURE HAPPY ETA INCREASES SFC DWPTS WELL ABOVE THE NGM... HENCE DECREASING THE STABILITY. PREFER TO TAKE AN AVERAGE OF THE TWO. MODELS SHOW A S/W EJECTING OUT OF WESTERN TROF REACHING CENTRAL ARKANSAS BY 48 HRS. SOME THUNDER COULD REACH INTO WESTERN SEMO ZONES BY LATE MONDAY BUT WILL HOLD OFF AND LEAVE DRY THRU MONDAY. EXTENDED HAS NO MENTION OF PRECIP UNTIL THURSDAY FOR WESTERN SECTIONS AND MAY TWEAK THIS A BIT BASED ON AVN. .PAH...NONE. SDB
FXUS63 KLMK 090729 ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON 1000 AM EDT SUN MAY 9 1999 CURRENT FCST ON TRACK. 12Z RUC AND 03Z MESO-ETA OFFER NO SURPRISES AS SHORTWAVE TRACKS ACROSS PA/NY THIS AFTERNOON WITH THE TAIL END CLIPPING THE NE ZONES DURING THE AFTERNOON. VORT THEN MVS WELL E OF THE AREA BY EVENING. SATELLITE IMAGERY INDICATES MOST OF THE CLOUDS ASSOCIATED WITH THIS FEATURE ARE N OF THE AREA AND OVR THE MTNS. 700MB TO 500MB LAPSE RATES INCREASE A BIT THIS AFTERNOON...BUT GOOD CAP AND DEVELOPING DOWNSLOPING WINDS SHUD PREVENT ANYTHING MORE THAN SOME CU. WILL CALL THE FAR NW ZONES AND ZONES BORDERING PA P/SUNNY WITH M/SUNNY ELSEWHERE. 12Z LAMP DATA AND 12Z RUC SUPPORT CURRENT MAX TEMP FCST. LAPS DATA SHOWS WEAK LEESIDE TROF AT THE SFC. SFC WINDS E OF THIS TROF ARE QUITE VRBL ATTM. HOWEVER...XPCT WINDS JUST OFF THE SFC TO MIX OUT THIS TROF DURING THE AFTERNOON. IN ADDITION...PASSAGE OF SHORTWAVE TO OUR N WILL CAUSE WINDS TO TURN NW. .LWX...NONE. WALSTON
FXUS61 KLWX 090656 md AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE/WASHINGTON 300 AM EDT SUN MAY 9 1999 KLWX RADAR SHOWED A FEW LIGHT SHOWERS OVER NORTHERN MD FROM 04Z-06Z.. BUT THE PRECIP HAS DISSIPATED QUICKLY OVER THE PAST HOUR. IR LOOP SHOWING AC DECK BREAKING UP OVER EASTERN 2/3 OF FA... WITH CONTINUING OVERCAST SKIES OVER THE WEST. WV LOOP SHOWING MID LEVEL SHORT WAVE OVER NERN PA AT TIME.. IN GOOD AGREEMENT WITH 00Z ETA AND NGM. 00Z ETA/NGM AND 03Z RUC SHOW VORT CENTER MOVING ACROSS CENTRAL PA THROUGH THE MORNING. WEAK PVA REACHING INTO THE FAR NORTHEASTERN SECTIONS OF THE AREA THROUGH 12Z.. WITH NVA THEREAFTER. LAPS DATA SHOWING INCREASING DOWNSLOPE FLOW FROM THE SURFACE THROUGH 850 MB... AND THIS SHOULD RESULT IN A CONTINUED CLEARING TREND OVER THE AREA THROUGH DAYBREAK. CLOUDS MAY HOLD ON A LITTLE LONGER FOR WESTERN TIER OF COUNTIES... AND WILL REFLECT THAT IN ZONES. MODEL SOUNDINGS INDICATE DECENT LAPSE RATES THIS AFTERNOON AND ENOUGH MOISTURE FOR SOME SCT CU TO DEVELOP... BUT MID LEVEL CAP WILL KEEP THINGS FROM GETTING OUT OF HAND. WEAK HIGH PRESSURE AND CONTINUED DOWNSLOPE FLOW WILL RESULT IN CLEAR SKIES TONIGHT AND MONDAY. RIDGING WORKING INTO AREA TOMORROW SHOULD PUSH TEMPS UP A COUPLE OF DEGREES OVER TODAYS HIGHS... ESPECIALLY FOR SWRN HALF OF FA. WILL HAVE TO WATCH WINDS THIS AFTERNOON AS MODEL SOUNDINGS SHOW 15-20 KTS MIXING DOWN TO THE GROUND. NO MARINE FLAGS ANTICIPATED AT TIME..HOWEVER. .LWX...NONE. MARGRAF! md AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1130 AM EDT SUN MAY 9 1999 MAIN FCST QUESTIONS FOR THIS AFTERNOON CONCERN CLOUDS/TEMPS. VIS LOOP INDICATED PATCH OF AC/CI OVER NRN MN STREAMING TOWARD UPR MI. HOWEVER...CLOUDS ENCOUNTERING AREA OF SUBSIDENCE AND ISENTROPIC DESCENT DOWNSTREAM OF MID LVL RDG AXIS. ALTHOUGH CLOUDS SHOULD THIN OUT AS THEY MOVE EAST...PER 12Z RUC 700-400 RH FCST...ENOUGH WILL SURVIVE TO MENTION PTSUNNY OVER WRN 1/3 OF UPR MI. SFC DEWPOINTS GENERALLY IN THE UPPER 20S F...NOT CONDUCIVE TO CU FORMATION WITH H85 TEMPS INCREASING INTO 2-4C RANGE THIS AFTERNOON. SOME CU EARLY OVER ERN UPR MI WHERE COLDEST AIR LINGERED. THESE ARE ALREADY THINNING OUT AS STABLE AIR OFF OF LAKE FLOWS ONSHORE. SFC RDG AXIS FROM NRN MANITOBA THROUGH NRN MN INTO WI FCST TO SLIDE GRADUALLY EAST. WEAKENING NW GRADIENT FLOW...950 WINDS DROPPING AOB 10 KTS BTWN 18Z-24Z...WL ALLOW LK BREEZES TO SET UP THIS AFTERNOON. WL BOOST INLAND TEMPS A NOTCH WITH TREND TOWARD SLIGHTLY WARMER 900-850 TEMPS WITH RUC. .MQT...NONE. JLB
FXUS63 KGRR 091526 mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 900 AM CDT SAT MAY 8 1999 SFC ANALYSIS INDICATES SFC RIDGE ACROSS ERN MN THIS AM. 12Z RAOB FM MPX IS VERY DRY IN THE LOW LAYERS...AND THIS SHOULD HELP ENHANCE VERTICAL MIXING LATER IN THE DAY. GRADIENT IS FAIRLY WEAK ATTM... BUT SLOW EWD MOVEMENT AND DEEPENING OF SFC LOW IN NE CO/SW NEB SHOULD ALLOW SE WND TO INCREASE...ESP THIS AFTN IN SW MN. SIGNIFICANT THETA-E GRADIENT TO THE SW WILL ADVECT NWD THIS AFTN. 12Z RUC SHOWS AN INCREASE IN WAA AND MOISTURE ADVECTION ACRS WRN MN AFT 21Z. CURRENT ZFP INCLUDES A SLIGHT CHC OF POPS...AND THIS LOOKS REASONABLE. WILL UPDATE ZONES TO REMOVE MORNING FOG...REALIGN HIGHS SLIGHTLY BASED ON SOUNDINGS...AND ADJUST SKY COVER WORDING. .MSP...NONE. DAVIS
FXUS63 KMPX 090819 mn FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 940 AM CDT SUN MAY 9 1999 .CURRENT SYNOPTIC OVERVIEW... 12Z U/A PLOTS INDICATED CURRENT PRECIPITATION OVER CWFA BEING ENHANCED BY 60 KT MID-LEVEL SPEED MAX AND INCREASING DIVERGENCE ALOFT. 13Z SURFACE AND STREAMLINE ANALYSIS DEPICTED RIDGE AXIS FROM LAKE WINNIPEG TO NEAR DULUTH. KMVX VAD WIND PROFILE INDICATED ISENTROPIC LIFT INITIATING AROUND 4KFT. .SHORT TERM... 12Z RUC SUGGESTS AXIS OF GREATEST THETA-E ADVECTION AND 85H MOISTURE FLUX CONVERGENCE TO REMAIN SOUTH THROUGH AFTERNOON. WILL CHECK OVER NEW MODEL RUNS BEFORE PASSING JUDGEMENT ON INHERITED ZONE PACKAGE. .FGF...NONE. BERG
FXUS63 KFGF 091134 nd FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 630 AM CDT SUN MAY 9 1999 WILL UPDATE ERN ND ZONES TO REFLECT CURRENT RADAR WITH AREA OF PCPN MOVING ENE OUT OF CNTRL ND. WILL NEED TO WORD SOME ZONES AS A PERIOD OF RAIN THIS MORNING. STILL HAVE LOW CONFIDENCE ON HOW FAR THIS PCPN WILL GET...SATELLITE DOES SHOW WARMING TOPS AND PCPN IS RUNNING INTO DRY AIR IN THE LOW AND MID LEVELS. ETA APPEARED TO HAVE BETTER QPF REFLECTION THIS AM...HAVING PCPN INTO ERN ND BTWN 12 AND 18Z AND THEN SHUTTING IT OFF AS FOCUS RETURNS OUT WEST. THIS APPEARS REASONABLE AS 09Z RUC PUSHES 50H VORT MAX THRU ERN ND ERLY THIS MORNING FOLLOWED BY NVA. UPDATE OUT SOON. .FGF...NONE. RIDDLE
FXUS63 KBIS 090846 nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON SC 944 AM EDT SUN MAY 9 1999 NO SIG CHANGES TO CURRENT FORECAST. WEAK SFC TROF EXTENDS FROM NC COAST SWRD TO JAX AND ACROSS FL INTO GULF OF MEX CAUSING NO SIG WX BUT W TO NW WINDS ALONG COAST. WEAK NW FLOW WILL ALLOW BEACHES TO WARM MORE THAN YESTERDAY BEFORE SEABREEZE KICKS IN AND DROPS TEMPS. DRY 12Z CHS SOUNDING...0.83 PW. ONLY CLOUDS OVR CWA ATTM FROM CIRRUS BLOWOFF FROM GULF OF MEX CONVECTION. EXPECT A FEW CU THIS AFTERNOON AS TEMPS CLIMB AND WEAK UPPER LEVEL VORT OVER UPSTATE SLIDES NEWRD AND ENHANCES LIFT SLIGHTLY AS SEABREEZE CONVERG LINE DVLPS ALONG COAST. WILL GO MOSTLY SUNNY THIS AFTERNOON. VORT MAX OVER ST LOUIS STALLS ALONG SE U.S. COAST BY LATE MON. LLVL MOISTURE INCREASE WITH ONSHORE FLOW LATE TUE INTO WED WL START TO INCREASE CLOUDS AND POPS MIDWEEK ONWARD. CWF...WL NEED TO MAKE SOME CHNGS TO WIND DIR FOR UPDATE. RUC LOOKS TO BE DOING A GOOD JOB AND WL LEAN TOWARDS ITS OUTPUT. WINDS INITIALIZE NW AND BCM VAR OVR THE CSTL WTRS. WL INITIALIZE HARBOR NW...QUESTION IS THE RESULTANT WIND DIR AND SPEED. WL IT BE STRONG ENOUGH TO OVR POWER THE MEAN WIND. WL GIVE A SOUTHERLY DIR TO SEA BRZ THIS AFTERNOON. .CHS... SC...NONE. GA...NONE. JCI/SLB
FXUS62 KGSP 091307 sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MIDLAND TX 1049 AM CDT SUN MAY 9 1999 A STRONG SOUTHERLY FLOW OF MOISTURE CONTINUES OVER THIS REGION. 15Z SURFACE MAP SHOWS THE MOISTURE EAST OF A BIG BEND...TO EAST OF GDP...TO ATS....WITH DEWPOINTS RANGING FROM GREATER THAN 50F TO THE MID 60S PERMIAN BASIN TO SOUTH PLAINS. STREAMLINES ON AWIPS SHOW THE DRYLINE WAS SETTING UP NEAR THE ABOVE POINTS. IT SHOULD AS IS USUALLY THE CASE HERE MOVE SOMEWHAT FURTHER EASTWARD THIS AFTERNOON BEFORE RETREATING TONIGHT. THE 12Z RUC INDICATED IT SHOULD EXTEND FROM THE EASTERN BIG BEND...TO NEAR MAF...TO NEAR SEMINOLE. 12Z RAOB DATA INDICATED A FEW DEGREES COOLING ALOFT AT 7H AND 5H ALONG WITH SLIGHT HEIGHT FALLS. THE RUC CONTINUES THIS COOLING TREND ...ALONG WITH THE LEFT FRONT PORTION OF THE 3H/25H SPEED MAX OVER THE BIG BEND BY 00Z. THUS A CHANCE OF SEVERE WX EXISTS FOR LATER TODAY AND THIS EVENING...AS NOTED IN SPC MESOSCALE DISCUSSION AND OUTLOOK. WITH THIS IN MIND...OUR T-STORM OUTLOOK WILL BE UPDATED AROUND NOON CENTRAL TIME. NEW WORK ZONES ARE ON THE WAY. BOYD
FXUS74 KEWX 091547 tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BLACKSBURG VA 105 PM EDT SUN MAY 9 1999 HIGH RH AND A STRONG SHORTWAVE CAUSED SKIES TO BECOME MOSTLY CLOUDY OVER SOUTHEASTERN WV AND THE WESTERN NRV. TODAY...H8-H5 LAPSE RATES NOT TERRIBLY IMPRESSIVE BUT AS HIGH AS 23-25. 15Z RUC HAS PERSISTANT HIGH H8 RH...ALTHOUGH SLOWLY SINKING SOUTHWARD. VIS SAT PIX HAS MOST DENSE CLOUD DECK OVER SERN WV WITH LOTS OF BREAKS TO THE NORTH AND WEST. SOME OF THIS DRIER AIR MAY SLOWLY WORK IN TODAY BUT WILL BE ENOUGH CLOUDS TO LOWER MAXS AND BIT AND MAKE FOR A GREYER DAY IN THE WESTERN THIRD. POTENT SHORTWAVE DIVING THROUGH SOUTHWESTERN TN ATTM WILL REMAIN WELL TO THE SOUTH OF SWRN CWA WITH ANY SHRA/TSRA SUPPRESSED TO THE SOUTH BY JET STREAK ROUNDING BASE OF TROUGH NOW LIFTING THROUGH NEW ENGLAND. WILL ISSUE QUICK UPDATE. .RNK... VA...NONE. NC...NONE. WV...NONE. NOGUEIRA
FXUS71 KRLX 091441 va AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 257 AM EDT SUN MAY 9 1999 LOOKS LIKE A NICE OUTDOOR DAY TODAY. WV SHOWS A NICE SWIRL CENTERED ACRS ERI WHILE ANOTHER S/W IS LOC NR STL. BELIEVE THE MD LVL CLDS NOSING INTO WRN FRNG OF CWA ARE ASSICIATED WITH THE NRN VORT. DOWNSLOW FLOW IS ERODING THE ERN EDGE OF THESE CLDS. SO REALLY DO NOT XPCT MUCH OF AN ERWD PROG OF THE CLDS AS THE VORT MVS E. AT THE SFC...A WK BNDRY IS SLICING ACRS OH SW ALNG THE OH RIV. RUC AND MESO ETA PICK UP ON THE BNDRY AND BRNG IT ACRS THE CWA THIS AFT AND EVE. ONLY A THN LYR OF MID LVL MOIST IS ASSOC W/ SRN PORTION OF THE BNDRY. HWVR WITH DOWNSLOP FLOW...DO NOT XPCT MUCH IN THE WAY OF CLD DEV AND SHULD ONLY SEE A WND SHIFT W/THE BNDRY PASSAGE. SO WL STICK WITH MS COND. FOR TON...THE BNDRY MOVS S INT NC AND TN WHILE A HI BLDS IN FM THE GT LKS. AT MD LVLS...THE NRN S/W SLIPS OFF THE NEW ENGLAND CST WHILE THE SRN S/W PROGRESSES SE INTO TN AND SC. SO LOOKS AS THOUGH VA WL REMAIN DRY. TSECTS DO INDICATE SOME CI TON AND SUN THOUGH THUS WL GO W/MCLR TON AND MS ON SUN RATHER THAN SUNNY. TEMPWISE...NW FLOW WL CONT TON AND GRADUALLY BEC NE ON SUN. WITH BAY AND OCEAN TEMPS STILL ON THE COOL SIDE...WL SEPARATE OUT THOSE ZNS. OTHERWISE FAN AND MOS LOOK REASONABLE. CWF...WNDS BECMG NW TODAY TO N TONIGHT AND NE ON SUN. .AKQ...NONE. SHADE
FXUS71 KRLX 090646 va NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DENVER COLORADO 935 PM MDT SUN MAY 9 1999 COLD FRONT BLEW THRU DEN METRO AREA ARND 02Z THIS EVENING WITH NLY GUSTS TO 30KTS. FRONT ALSO USHERED MUCH HIGHER DEW POINTS WITH THE DWPT AT DEN JUMPING FM -02C TO +08C DURING HR FOLLOWING FROPA. FRONT IS XPCTD TO CONT ITS SWRD PROGRESS OVRNGT WITH DWPT SPREADS PSBLY APCHG ZERO ON THE PLAINS AFT MIDNIGHT RESULTING IN AREAS OF STRATUS AND FOG. DEN 88D VAD WND PROFILER AS OF 03Z SHOWED NELYS UP TO 9 THSND FT ASL. LATEST RUC (00Z RUN) HAD SFC-750 MB WNDS ALG THE FNT RNG BACKING TO NWLY DIR AFT 06Z WITH PASSAGE OF 7H TROF AXIS. INTERESTING HOW RUC INCREASES SFC-5H RHS OVR FNT RNG URBAN CORRIDOR OVRNGT WITH NWLY DOWNSLOPE FLOW. OBVIOUSLY OTHER THINGS ARE GOING ON SUCH AS MID-LVL QG FORCING AND DESTABLIZATION. BELOW 750 MBS RUC SHOWS RHS RISING OVRNGT ACRS THE NERN PLNS WITH RHS EXCEEDING 80 PCT WITHIN THE SOUTH PLATTE RVR BASIN FM JUST NE OF THE DEN METRO AREA TO JULESBURG ON NE LINE. THIS IS WHERE WE'LL LKLY TO SEE AREAS OF FOG AND STRATUS FORMING LATER TNGT. OTWS CURRENT FCST STILL ON TRACK... ALTHOUGH T-STORM CHCS LOOK SLIM AT THIS TIME EXCEPT NR NERN BORDER (I.E. PHILLIPS AND SEDGWICK CTYS) WHERE DERIVED SFC BASED CAPES AS OF 03Z NR 1200 J/KG IN AREA OF STG LOW LVL CONVERGENCE ALG SFC COLD FNT. WILL CONT TO MONITOR THIS AREA FOR TSTORM DVLPMNT NXT 2-3 HRS. BAKER .DEN...NONE.
FXUS65 KBOU 092031 co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 944 PM EDT SUN MAY 9 1999 BENIGN BUT COOL OVERNIGHT ON TAP FOR FORECAST AREA. LATEST MSAS CHART HAS HIGH PRESSURE CENTERED OVER MICHIGAN...WITH A WEAK PRESSURE GRADIENT OVER MUCH OF THE STATE. SATELLITE IMAGERY SHOWED A FAIRLY WIDE BAND OF CIRRUS SPILLING OVER UPPER RIDGE...EXTENDING FROM STRONG CONVECTION IN NORTHERN PLAINS ACROSS UPPER MICHIGAN AND INTO NORTHEAST HALF OF LOWER MICHIGAN. MAIN CONCERNS OVERNIGHT CENTER ON AMOUNT OF CLOUD COVER AND THE RESULTING EFFECT ON LOW TEMPERATURES. BAND OF CIRRUS IS CAPTURED WELL BY RUC ON 500-300MB LAYER RH PROG. MAIN CLOUD BAND IS CONFINED TO 40 PERCENT AND GREATER RH VALUES AND THESE ARE FORECAST TO GENERALLY REMAIN ACROSS THE SAME AREA OVERNIGHT. SOME OF THE CIRRUS HAS BEEN FAIRLY THICK...SO WILL UPDATE FORECAST TO PARTLY CLOUDY FOR AREAS NORTH OF A LINE FROM TRAVERSE CITY TO STANDISH. TEMPERATURES HAVE STARTED TO FALL QUICKLY WITH LOSS OF INSOLATION. AREA DEW POINTS OVERNIGHT WILL GENERALLY BE AROUND 30 DEGREES AND WINDS ARE/WILL BE LIGHT AND VARIABLE. AS A RESULT...WILL DROP OVERNIGHT LOWS A NOTCH ALL ZONES. THERE MAY BE ENOUGH CLOUD COVER TO TEMPER RADIATIONAL COOLING SOME...BUT FEEL THESE EFFECTS WILL BE MINIMAL. .APX...NONE. BAK
FXUS63 KMQT 091950 mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1130 AM EDT SUN MAY 9 1999 MAIN FCST QUESTIONS FOR THIS AFTERNOON CONCERN CLOUDS/TEMPS. VIS LOOP INDICATED PATCH OF AC/CI OVER NRN MN STREAMING TOWARD UPR MI. HOWEVER...CLOUDS ENCOUNTERING AREA OF SUBSIDENCE AND ISENTROPIC DESCENT DOWNSTREAM OF MID LVL RDG AXIS. ALTHOUGH CLOUDS SHOULD THIN OUT AS THEY MOVE EAST...PER 12Z RUC 700-400 RH FCST...ENOUGH WILL SURVIVE TO MENTION PTSUNNY OVER WRN 1/3 OF UPR MI. SFC DEWPOINTS GENERALLY IN THE UPPER 20S F...NOT CONDUCIVE TO CU FORMATION WITH H85 TEMPS INCREASING INTO 2-4C RANGE THIS AFTERNOON. SOME CU EARLY OVER ERN UPR MI WHERE COLDEST AIR LINGERED. THESE ARE ALREADY THINNING OUT AS STABLE AIR OFF OF LAKE FLOWS ONSHORE. SFC RDG AXIS FROM NRN MANITOBA THROUGH NRN MN INTO WI FCST TO SLIDE GRADUALLY EAST. WEAKENING NW GRADIENT FLOW...950 WINDS DROPPING AOB 10 KTS BTWN 18Z-24Z...WL ALLOW LK BREEZES TO SET UP THIS AFTERNOON. WL BOOST INLAND TEMPS A NOTCH WITH TREND TOWARD SLIGHTLY WARMER 900-850 TEMPS WITH RUC. .MQT...NONE. JLB
FXUS63 KGRR 091526 mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 900 PM CDT SUN MAY 9 1999 00Z RUC CROSS SECTION OF THETA-E SHOWS VERY THICK LAYER OF STABLE AIR NEAR THE SURFACE...AND THETA-E DECREASING WITH HEIGHT ABOVE 800 MB ACROSS WESTERN MN...FOR BOTH 09Z MON AND 12Z MON. HOWEVER...CROSS SECTIONS ACROSS EASTERN MN AND WESTERN WI DON'T SHOW THETA-E DECREASING WITH HEIGHT. THUS POPS FOR TONIGHT REFLECT EXPECTED ELEVATED INSTABILITY DISTRIBUTION. NELEIGH PROFILER SHOWED 850 MB WIND OF 50 KTS...CONTRIBUTING TO THE ISENTROPIC LIFT ACROSS WESTERN MN TONIGHT. SO...LIKELY POPS ACROSS WESTERN MN JUSTIFIED FOR TONIGHT. CHANGED MOSTLY CLOUDY TO BECOMING MOSTLY CLOUDY ACROSS EASTERN MN AND WESTERN WI BASED ON METARS AND IR SATELLITE IMAGERY. WITH THE CONTINUING WARM ADVECTION...THE CLOUDS SHOULD FORM OVERNIGHT. OVERALL...MINIMAL CHANGES TO LATE AFTERNOON PACKAGE. .MSP...NONE. NAISTAT
FXUS63 KMPX 092010 mn MOJAVE DESERT/SOUTHERN GREAT BASIN AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LAS VEGAS NV 905 PM PDT SUN MAY 9 1999 SYNOPSIS...A WEAK FRONT EXTENDING FROM NORTHERN UTAH INTO EXTREME SOUTHERN NEVADA WILL DRIFT SOUTH INTO ARIZONA AND WEAKEN. GUSTY NORTH WINDS WILL DEVELOP DURING THE MORNING HOURS MONDAY THEN GRADUALLY DIMINISH DURING THE LATE AFTERNOON AS THE PRESSURE GRADIENT WEAKENS. MOIST NORTHWEST FLOW ALOFT WILL ALLOW CONSIDERABLE HIGH CLOUDS TO OVERSPREAD THE REGION MONDAY. TEMPERATURES WILL REMAIN NEAR SEASONAL NORMS THE NEXT FEW DAYS. DISCUSSION...SURFACE FRONT HAS BEEN HUNG UP ACROSS THE LV VALLEY ALL EVENING. NORTH VALLEY SITES REPORTING NW WINDS WHILE MACCARRAN STILL HAS WSW WINDS. RUC INDICATING ISENTROPIC UPGLIDE THRU THE 320-325K THETA LAYER WITH RELATIVELY LOW AMOUNTS OF LIFT REQUIRED TO SATURATE. HENCE CONSIDERABLE HIGH CLOUDS CONTINUE TO STREAM THRU BASE OF UPPER TROUGH. THIS PATTERN EXPECTED TO PERSIST GIVEN DIRTY RIDGE UPSTREAM. UPPER LOW COOLED DRA SOUNDING BY ABOUT 3-5 DEG C FROM 800-550MB AND SOME COOL AIR MAY FILTER INTO EXTREME SOUTHERN NV TOMORROW BUT SHOULD MODIFY FAIRLY QUICKLY AS HGTS/THKNS BEGIN TO RISE MONDAY EVENING INTO TUESDAY. CURRENT ZONES MENTION PARTLY CLOUDY MOST AREAS FOR MONDAY. BELIEVE WE WILL SEE FAIRLY WIDESPREAD HIGH CLOUD COVERAGE BUT DO NOT SEE ANY REASON TO UPDATE FOR A ONE-CATEGORY CHANGE IN THE 2ND PERIOD. WILL ALLOW MIDSHIFT TO EVALUATE SITUATION AND MAKE FINAL DECISION. RUNK .LAS...NONE.
FXUS65 KREV 092201 nv AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC 844 PM EDT SUN MAY 9 1999 WEAK AND ILL-DEFINED BOUNDARY NOW LOCATED FROM ABOUT EDE-PGV-GSB. ABOUT THE ONLY DIFFERENCE IN THE AIRMASS BEHIND THE BOUNDARY IS SLIGHTLY LOWER DEWPOINTS AND A SUBTLE WIND SHIFT. RUC-II PEGGED THE POSITION OF THE BOUNDARY AT 00Z AND ONLY SLOWLY MOVES IT TO THE COAST BY 09Z. TEMPS/DEWPOINTS ARE STILL QUITE WARM AT THIS HOUR AND WILL ONLY FALL SLOWLY THRU THE EARLY MORNING HOURS...SO WILL BUMP UP MINS A CATEGORY AS ANY DROPS IN TEMPS WILL OCCUR TOWARD MORNING. OTHERWISE...GOING FCST LOOKS GOOD. MARINE...FCST LOOKS GOOD WITH NO REAL CHGS NEEDED. .MHX...NONE. COLLINS
FXUS62 KILM 100043 nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 843 PM EDT SUN MAY 9 1999 WV IMGRY SHOWS H5 S/WV ROLLING ACRS THE TN VLY THIS EVE. 21Z RUC2 CONTS THE TREND OF KEEPING THIS S/WV & MOST OF ITS ASSOC CLDS TO OUR S OVRNGT. CUD SEE A FEW ROGUE AC/CI MV OVR CWA. IN ADDITION...SUM CI FM CONVECTION TO OUR S CUD WANDER THIS WAY. WL MAINTAIN A MOCLR 1ST PD FCST. W/ 00Z DEWPTS IN THE 55-60 RANGE & GD RAD COOLING CONDS XPCTD...GOING FCST MINS LOOK FINE. CWF: LATEST RUC & LAMP PROGS CONCUR W/ GOING TRENDS BUT LATEST RA1 GRAPHIC SHOWS SMALLER SEAS S OF LTL RVR. KLTX VWP SHOWS 1K FT WINDS BECMG MORE SW ATTM. WL CHG INIT DIR & SEAS ACCORDINGLY. .ILM...NONE. LGE
FXUS62 KILM 091849 COR nc FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 910 PM CDT SUN MAY 9 1999 ...FORECAST CONCERNS...ADDNL TSRA...HEAVY RAIN... ELEVATED CONVECTION WITH ISOLD SVR STORMS AHEAD OF WARM FRONTAL BOUNDARY WITH VERY STRONG H8 WAA AND S/W FROM WV LOOP PROPAGATING EAST ACROSS NW AND WEST CENTRAL MN. IR LOOP AND KABR 88D INDICATING MORE CONVECTION UPSTREAM OVR CENTRAL SD MOVING THIS WAY. FROM 21Z RUC STRONG WAA CONTINUES AND AS H8 LOW AND WARM FRONT LIFT NORTH WITH SIGNIFICANT MOIST FLUX AND H8 THETA-E RIDGE THROUGH FA MORE TSRA LIKELY OVERNIGHT AFT BRIEF BREAK. HEAVY RAIN WILL COME INTO PLAY WITH SOME AREAS APPROACHING FFG THRESHOLD. WITH WIDESPREAD SMALL HAIL AND BRIGHT BAND CONTAMINATION 88D PCPN ESTIMATES UNRELIABLE. WILL BRIEF UPCOMING SHIFT ON PSBL WATER PROBLEMS WITH THE POTENTIAL FOR ADDNL WIDESPREAD PCPN. .FGF...NONE. VOELKER
FXUS63 KBIS 092038 nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 908 PM EDT SUN MAY 9 1999 SHORTWAVE/COLD POOL OVER TN SHOWS UP NICELY ON 18Z ETA AND 21Z RUC. BOTH MDLS MOVE THE FEATURE SE BUT KEEP IT WEST OF THE CWFA. ACTIVITY ASSOCIATED WITH THE FEATURE HAS BEEN ON THE DECREASE AS WELL. WILL REMOVE SPRINKLE WORDING FROM OUR WESTERN MTN COUNTIES. CLOUDS HAVE ACTUALLY INCREASED SOMEWHAT THE LAST FEW HOURS DUE IN PART TO MOISTURE CONVERGENCE AXIS ACROSS THE CWFA. MAY HAVE TO CONTINUE PARTLY CLOUDY WORDING OVERNIGHT. FCST TEMPS OUTSIDE OF THE MTNS ARE COOLER THAN MDL GUIDANCE...BUT CLOSE TO CURRENT DEW POINTS. WILL LEAVE AS IS. .GSP...NONE. RWH
FXUS62 KCHS 100103 sc AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD ...UPDATED FOR TIME OF ZONE UPDATE 850 PM CDT SUN MAY 9 1999 MID LVL DRY PUNCH ADVERTISED ON 21Z RUC...WITH LEADING EDGE ACCAS BAND...WITH WDLY SCT SHRA/TSRA MOVG THRU MAINLY NRN TIER OF CWA... AND N OF KSUX. CONVECTIVE THREAT IS AT FOREFRONT OF CONCERNS TNGT. ATM IS REALLY A LOADED GUN...ESPLY WRN CWA...WHERE LO LVL MSTR AND A VERY STEEP MIDLVL LAPSE RATE HAS RESULTED IN CAPE NR 2.5K...WITH LESS THAN 1C CAP. AIRMASS OF MUCH DIFFERENT CHARACTER TO E...WITH KOAX RAOB STRONGLY CAPPED. ANALYSIS OF MSTR TRANSPORT ON SAME RUC MDL INDICATES THAT MAIN THREAT AREA WILL REMAIN TO W OF KFSD FOR QUITE A WHILE WITH THE 60KT LLJ...AND MAY BE VERY LATE TNGT BEFORE ENTRG SW MN. LKLY ERN PART OF NW IA WILL HAVE VERY LTL THREAT OF CONVECTION AT ALL...ALTHOUGH THERE IS SOME BTTR MSTR CONVERGENCE AND ELEVATED INSTABILITY GENERATED AFT 09Z. SPC RECENTLY EXPANDED MDT RISK INTO WRN CWA...AND DO NOT HAVE ONE BIT OF ARGUMENT. WL LIKELY EXPAND ON TIMING OF SEVERE STRMS FM PREVIOUS ZN PACKAGE. LOOK FOR A PARTIAL ZONE UPDATE AWAY FROM EXPECTED NEW SVR WX WATCH BY 915...WITH REMAINDER OF UPDATE AFTR NEW WATCH ISSUANCE. .FSD...NONE CHAPMAN
FXUS63 KFSD 100152 sd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 220 AM CDT MON MAY 10 1999 06Z SFC ANALYSIS SHOWS RIDGE JUST TO OUR EAST WITH SYSTEM OVER CNTRL PLAINS. 06Z RUC SHOWS LOW OVER CO MOVG N INTO THE DAKOTAS...SO MORE SVR WX EXPECTED IN THOSE AREAS AGAIN TODAY. 00Z MODELS FAIRLY SIMILAR WITH UPPER RIDGE HOLDING IN OVER OHIO VALLEY/GREAT LAKES REGION. MAY SEE SOME STRAY CI MOVE INTO CWA...BUT WILL BE ON THE THIN SIDE...SO TODAY SHOULD BE MOSTLY SUNNY AND WARMER AS 850 TEMPS RISE TO AROUND 14...CURRENT FORECAST OF NEAR 80 STILL REASONABLE. TONIGHT...SYSTEM STILL REMAINS FAIRLY STAGNENT WITH A SLOW RETURN OF MOISTURE...BUT PCPN SHOULD REMAIN WEST OF MISSISSIPPI RIVER. CLDS WILL BE ON THE INCREASE WHICH WILL HELP KEEP TEMPS UP...IN THE UPPER 50S. PRELIMINARY CODED CITY FORECAST FOR COORDINATION... SPI UB 080/060 081/061 079 68002 PIA UB 079/060 080/060 078 68003 DEC UB 079/060 080/059 080 68002 CMI UB 079/058 080/058 080 6800- MTO UB 080/058 080/058 081 6800- LWV UB 080/059 081/058 081 6800- BYRD
FXUS73 KLOT 091925 il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TOPEKA KS 1016 PM CDT SUN MAY 9 1999 ...SEVERE CHANCES AND PRECIPITATION POPS ARE MAIN CONCERNS THIS FORECAST UPDATE... COORDINATION WITH SPC HAS LED TO CANCELING THE SEVERE THUNDERSTORM WATCH NUMBER 235. NEW 00Z RUC RUN HAS ESCENTIALLY DELETED ALL PRECIPITATION FROM THE CWA FOR THE REST OF TONIGHT. NEW REFLECTIVITY FORECAST THROUGH 08Z FROM PROJECT HUBCAP ALSO SHOWS AN ABSENCE OF PRECIPITATION OVER THE CWA THROUGH THAT TIME FRAME. AM A LITTLE CONCERNED OVER LOW LEVEL JET ACTIVITY LATER TONIGHT...BUT IN LIGHT OF THE LATEST RUC MODEL AND PROJECT HUBCAP DATA HAVE DECIDED TO LOWER POPS AND DIMINISH THREAT FOR SEVERE WEATHER SOMEWHAT THE REST OF THE NIGHT. .TOP...NONE LWS
FXUS63 KGLD 100306 AMD ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SHREVEPORT LA 230 AM CDT MON MAY 10 1999 RATHER BUSY ALREADY WITH ONGOING CONVECTION JUST WEST OF CWA AND NEWLY ISSUED TSTM WATCH 239 FOR OUR WESTERN MOST COUNTIES IN EAST TEXAS SO HERE IT GOES. MODELS CONTINUE TO SHOW SIMILIAR BREAKDOWN AND EASTWARD PROGRESSION OF UPPER RIDGE PATTERN ACROSS S CENTRAL PLAINS AS NEGATIVELY TILTED TROF BEGINS ITS SLOW EAST-NORTHEAST MIGRATION INTO OHIO VALLEY. AS PREVIOUSLY FCSTD...STRONG VORT MAX CONTINUES TO SEPARATE ITSELF IN RATHER WEAK SW FLOW ALOFT PATTERN ACROSS CNTRL TX INTO N OK. BOTH ETA AND NGM HAVE HAD CONSISTENT RUN TO RUN HANDLE ON THE EJECTION AND EVOLUTION OF THIS SHORTWAVE WITH THE AVN WEAKER AND FURTHER NORTH. FOR THIS REASON...WILL CHOOSE A BLEND OF NGM AND ETA FOR CURRENT FCST. 06Z ANALYSIS SHOWS CONVECTIVE INDUCED MESO HIGHS ACROSS CNTRL OK AND CNTRL TX WITH VIGOROUS BAROCLINIC CONVERGENCE BOUNDARY ORIENTED N-S FROM NEAR TUL AND MLC TO DFW AND HDO. THIS BOUNDARY MOVING E-NE NEAR 30 KTS WITH NEW CELLS DEVELOPING ALONG...BEHIND BOUNDARY. AXIS MOVING INTO AMPLE LOW LEVEL MOISTURE WITH DEWPOINTS IN THE LOWER 70S ACROSS ALL OF NE TX AND NW LA. 03Z RUC INDICATING LI'S (-5 TO -10) AND CAPE AOA 2000 J/KG THIS MORNING ACROSS WEST HALF OF FA...STRONG POSSIBILITY OF SVR CONVECTION TODAY ACROSS E TX...SE OK. SVR NOT OUTLOOKED ACROSS NW LA TODAY...PER SWODY1 BUT BELIEVE IT WARRANTS MENTION DUE TO AMOUNT OF INSTABILITY AND EASTWARD PROGRESSION OF MOISTURE AXIS. BELIEVE HEAVY RAIN TO BE GREATER POSSIBILITY WITH THIS SYSTEM DUE TO GENERALLY WEAK BUT HIGHLY DIFFLUENT PATTERN ALOFT AND PWS AOA 1.50 IN. INCREASING SOUTHERLY 8H FLOW SHOULD FURTHER ENHANCE HEAVY RAIN POTENTIAL...ESPECIALLY ACROSS E TX AND SE OK TODAY. NMC 24HR QPF PROGS INDICATING THIS WITH HEAVIEST RAINFALL AXIS ORIENTED ACROSS SE OK...SW AR...NE TX. CURRENT THINKING IS THAT CONVECTION ACROSS N TX THIS MRNG WILL WEAKEN AND GENERATE OUTFLOW BOUNDRIES FOR AFTN CONVECTION TO FORM ON FURTHER EAST SO WILL THEREFORE ALLOW MAX TEMPS TODAY TO RISE A LITTLE HIGHER THAN NGM MOS ACROSS N LA. FURTHER NORTH AND WEST...NUMBERS IN BALLPARK AND WILL LEAVE ALONE. SHORT WAVE TO MOVE SLOWLY EAST TNGT WITH SECOND ROUND IN THE WAY OF TSTM ACTIVITY EXPECTED TO DEVELOP ON TUE WITH ANOTHER VORT FINGER ROTATING AROUND GREAT BASIN LOW. MODELS INDICATE A LITTLE MORE SOUTHERLY PROGRESSION WITH THIS VORT MAX BUT WILL GET FIRST EPISODE OVER WITH TODAY BEFORE FCSTNG A HIGH POP IN THIRD PERIOD WITH THE WEAKER SECONDARY SHORT WAVE. PRELIMS TO FOLLOW... SHV 86/69/87/69 6432 MLU 88/68/87/68 4522 TXK 82/67/85/66 7422 TYR 81/69/85/68 7332 LFK 86/70/88/69 7342 13
FXUS64 KLCH 100648 la AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1010 PM EDT FRI MAY 7 1999 SURFACE HIGH HAS TRACKED JUST TO THE SOUTH OF THE FORECAST AREA. THE ASSOCIATED RIDGE BROUGHT DRY WEATHER TO UPPER MICHIGAN THIS EVENING. 12Z AREA SOUNDINGS CONT TO SHOW A STRONG INVERSION AT 750-800 MB LEVEL PRODUCING A STRONG CAP OVER THE FA. SURFACE LOW OVER NORTHEAST COLORADO SHOULD TRACK NORTHEAST. THE GREATEST 3HR PRESSURE FALL WERE OVER EASTERN SD. CYCLONIC CIRCULATION WITH THIS SYSTEM WAS PULL SOME WARM MOIST AIR INTO THE DKTS AND MN ATTM. THIS IS EXPECTED TO WORK EAST INTO THE FORECAST AREA ON MONDAY NIGHT. A CONCERN FOR TONIGHT IS THE THUNDERSTORMS FIRING OVER ERN DKTS AND NW MN. 300K ISENTROPIC ANLYS SHOWING FAIRLY GOOD LIFT OVER THAT AREA ATTM. RUC DATA ALSO SHOWING ULVL JET DIVERGENCE OVR ERN DKTS ALSO AND THIS WILL CONT IN THAT AREA THRU TNGT...BUT NOT PROGRESSING INTO UP UNTIL MON NGT. THE NORTHERN GREAT LAKES REMAIN UNDER THE FRONT RIGHT QUAD OF THE UPPER LEVEL JET CORE ...SUPPORTING MORE SUBSIDENCE OVER THIS AREA. MEAN 1000MB-850MB RH WILL REMAIN LESS THAN 70 PERCENT OVER FA TONIGHT...BUT HIGHER TO THE WEST. THE THUNDERSTORMS WERE BUILDING ALONG THE 850MB THETA E RIDGE ACROSS THE CENTRAL AND NORTHERN PLAINS. EXPECT THESE STORMS TO TRACK JUST TO THE EAST OF THE RIDGE LATER TNGT... HOWEVER...SHOULD STILL REMAIN OVER MN AND WI AND WEAKEN AND DIE AS THEY MOVE AWAY FM MOSITURE SOURCE. BY MON NGT EXPECT THE STORMS TO EDGE INTO THE UP. THUS WILL NOT ADD ANY TSTRMS TO THE FCST FOR TNGT OR MON. MON NGT STILL LOOK LIKELY FOR TSTRMS POTENTIAL FOR UP. WITH 300MB FLOW OVER UP...EXPECT TO SEE SOME BLOW OFF OF THUNDERSTORM TOPS TO SPREAD OVER UP TNGT. THUS WILL GO WILL INCREASING HIGH CLOUDS TONIGHT. THE INCREASING HIGH CLOUDS TNGT WILL CAUSE TEMPS TO NOT DROP AS LOW AS PREVIOUSLY FCSTD OVER WRN UP. .MQT...NONE. DLG
FXUS63 KAPX 100145 mi MISSOURI STATE FORECAST DISCUSSION NATIONAL WEATHER SERVICE ST LOUIS MO 340 AM CDT MON MAY 10 1999 MDLS STILL HAVING TROUBLE PINNING DOWN FTRS...BUT 00Z RUNS APR TO BE COMING A LTL MORE IN AGREEMENT. WL USE A BLEND OF AVN/ETA... WITH STGR AVN LKG BEST WITH DYNAMICS OVR N PLAINS...WHILE ETA CERTAINLY PROVIDING BTR DETAIL IN ERY PART OF FCST CYCLE WITH PCPN ONGOING OVR OK/TX. STLT AND 88D TRENDS INDICATE THAT CNVTN OVR OK AND TX...AND WELL DEFINED OUTFLO PUSHING S OF RED RVR...IS TRYING TO SHUT DOWN PCPN OVR S KS AND HEADING INTO SW MO. THINK THIS TREND MAY CONT THRU THE MRNG HRS...CERTAINLY LIMITING AMT AND CVG OF PCPN. HWVR... ETA 7H AND 5H PROGS INDICATE THAT SHTWV WL CONT TO PROVIDE SM LFT TO CNTRL MO THRUOT DAY...AND WITH SUSTAINED S LO LVL FLOW PROVIDING SM MOISTURE AND MODEST AMTS OF INSTABILITY TO AMS DONT THINK PCPN THRT IS ENTIRELY OUT OF THE QUESTION. LO POPS AS FAR E AS A UIN-UNO LN STILL APRS REASONABLE AND WL CONT WITH THESE TRENDS. LTST RUC ALSO SUPPORTS ABV THINKING. WHILE LO POP THRT MAY CONT AHD OF ABV SHTWV TNGT...MAIN PCPN THRT PDS 2 AND 3 WL BE FOCUSED ALG SFC CDFNT OVR PLAINS AND UPR MSVLY. SERIES OF SHTWVS ROTATING ARND UPR LO SHUD KICK OFF A GD DEAL OF CNVTN TNGT ALG THIS FNTL BDRY THAT WL GRDL PUSH EWD AND BGN THREATENING PARTS OF LSX CWA ON TUE. WITH MAIN DYNAMICS RMNG WELL NW OF AREA...AND WITH RDGG FROM W GTLKS TO OHIO VLY E TRANSLATION OF PCPN MAY BE SLO. CHC POPS STILL LK GD...WITH BEST THRT W/NW SECTIONS OF CWA. GOING TEMP TRENDS LK TO BE ON THE MARK. .STL...NONE TRUETT
FXUS63 KMCI 100842 mo NORTHEAST MONTANA AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 855 PM MDT SUN MAY 9 1999 UPPER LEVEL TROUGH CONTINUES TO DIG TOWARDS SOUTHERN UTAH TONIGHT RESULTING IN SOUTHERLY FLOW ALOFT FOR THE FORECAST AREA. 00Z RUC IN GOOD AGREEMENT WITH 21Z RUC AND 12Z AVN. INVERTED SURFACE TROUGH WILL REMAIN ACROSS MUCH OF THE AREA TONIGHT AS A SURFACE LOW LIFTS NORTHEAST INTO SOUTH DAKOTA. MEANWHILE...50H AND 70H LOWS WILL REMAIN NEARLY STATIONARY ACROSS WEST CENTRAL AND NORTH CENTRAL MONTANA RESPECTIVELY. AREA RADARS AND SURFACE OBS SHOWING THE -RA HAS LET UP WITH WATER VAPOR IMAGERY INDICATING SOME DRYING ACROSS THE AREA. SNOW HAS STOPPED IN THE ZORTMAN AREA SO WILL DROP CURRENT SNOW ADVISORY. PRECIPITATION SHOULD BE ON THE INCREASE TOMORROW AS THE LOWS MOVE EAST AND WE GET SOME WRAP AROUND EFFECT. UPDATES ON THE WAY. WATERHOUSE GGW 5964 038/045/034/050 GDV 5984 037/046/035/054
FXUS65 KBYZ 100248 mt EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE TULSA OK 835 PM CDT SUN MAY 9 1999 REGIONAL RADARS ARE SHOWING LINE OF STORMS/BOW ECHO MAKING STEADY EASTWARD PROGRESS FROM SW TO N-CNTRL OK THIS EVNG. HAVE UPDATED ZONES TO REMOVE "AFTER MIDNIGHT" WORDING ACROSS MOST OF ERN OK. ALSO BUMPED POPS TO CATEGORICAL LEVELS WHERE WW IS CURRENTLY IN EFFECT BASED ON RADAR TRENDS. AT CURRENT SPEED...TSRA SHOULD REACH OSAGE/PAWNEE COUNTIES AROUND 930 PM. ASIDE FROM THE OBVIOUS RADAR TRENDS...INSTABILITY ANALYSIS SHOWS MORE STABLE AIR CLINGING TO FAR ERN OK/NW AR...WHERE A DRIER LOW-LEVEL AIR MASS CONTINUES TO BE ADVECTED IN FROM THE EAST. 21Z RUC INSISTS ON THIS MORE STABLE AIR MASS REMAINING IN PLACE THROUGH 09Z...AND I SEE LITTLE REASON THAT THIS AREA WOULD RAPIDLY DESTABILIZE IN THE NEXT FEW HOURS. THEREFORE...CURRENT ACTIVITY MAY TRY WEAKENING AS IT MOVES EAST OF U.S. HWY 75 INTO MORE STABLE AND DRIER AIR MASS. 18Z ETA ALSO SHOWS CAPPING INVERSION HOLDING STRONG IN SE OK OVERNIGHT...SO CONVECTION WILL LIKELY HOLD BACK BEFORE MAKING A RUN AT SE OK LATE TONIGHT. STRONGER CAP IN SE OK WILL ALSO KEEP ACTIVITY LESS WIDESPREAD WHEN IT DOES TRY MOVING EAST. BY THEN...DIURNAL COOLING AND WEAKER INSTABILITIES WILL KEEP ACTIVITY BELOW SEVERE LEVELS. SPEAKING OF THE SEVERE THREAT...AREA WIND PROFILERS SHOW WEAK MID-LEVEL WINDS AND LESS-THAN-IMPRESSIVE LOW LEVEL VEERING OF THE WINDS. CONVERGENCE ALONG A STRENGTHENING LOW-LEVEL JET OVER CNTRL/ERN OK MAY HELP MAINTAIN ACTIVITY...BUT ALL OTHER SIGNS POINT TO A WEAKENING TREND ONCE THE LINE OF TSRA PASSES U.S. HWY 75. MAY NEED TO UPDATE ZONES AGAIN LATER THIS EVNG TO LOWER POPS IN SE OK. FCSTID = 22 .TUL... AR...NONE. OK...SEVERE THUNDERSTORM WATCH UNTIL MIDNIGHT FOR ZNS 54...59...64.
FXUS64 KTSA 092104 ok AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 220 AM EDT MON MAY 10 1999 ONLY FEATURE OF NOTE THIS FORECAST IS CLOSED CIRCULATION OVER AL. RUC AND FRIENDS IN AGREEMENT THAT THIS FEATURE WILL NOT HAVE MUCH EFFECT ON FA OTHER THAN SOME SCATTERED CU FROM COLD POOL ALOFT. SURFACE RIDGE BUILDS...MAINTAINING DRY AIR MASS OVER REGION. TEMPERATURES SHOULD BE ABOUT SAME OR A CAT HIGHER THAN SUNDAY. FWC/FAN IN SAME BALLPARK AS CURRENT FORECAST AND WILL NOT CHANGE MUCH. WILL NOT MAKE ANY CHANGES TO EXTENDED AT THIS TIME. DELGADO .GSP...NONE.
FXUS72 KCAE 100558 sc SOUTH TEXAS FORECAST DISCUSSION 255 AM CDT MON MAY 10 1999 LINE OF THUNDERSTORMS ON OUR DOOR STEP. THIS TRIGGERED IN LARGE PART BY STRONG VORT MAX AS SHOWN IN RUC MODEL. THE VARIOUS MODELS CALL FOR VORT MAXES TO CONTINUE TO MOVE THROUGH AREA WITH TIMING MODEL DEPENDENT. NO CHANGE OF AIR MASS. WILL THEREFORE BROAD BRUSH WITH SLIGHT TO CHANCE POPS NEXT COUPLE OF DAYS. TEMPS PRETTY CLOSE TO GUIDANCE. PRELIMINARY NUMBERS... AUS 86/71/87/71 4332 SAT 87/72/88/72 3332 DRT 91/68/92/70 3222 .SAT...NONE. 03/18 MESO
FXUS64 KBRO 100749 tx EXTREME SOUTHWESTERN CALIFORNIA AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN DIEGO CA 900 AM PDT MON MAY 10 1999 A DECREASING MARINE LAYER AND WEAKER ONSHORE FLOW WILL RESULT IN BETTER CLEARING OF NIGHT AND MORNING LOW CLOUDS AND LOCAL FOG WEST OF THE MOUNTAINS. OTHERWISE...UPPER LEVEL HIGH PRESSURE BUILDING OFF THE COAST WILL KEEP THE WEATHER FAIR WITH WARMER DAYS INTO MID WEEK. AS EXPECTED...ANOTHER EDDY DEVELOPED OFFSHORE OVERNIGHT BUT DOES NOT APPEAR TO BE AS STRONG AS THE EDDY ON SUNDAY. PLUS...THE EDDY IS WEST OF SAN CLEMENTE ISLAND. THE 12Z RUC AND THE 03Z MESO ETA INDICATE THE EDDY WILL BE GONE THIS AFTERNOON. HOWEVER...GUSTY NORTHWEST WIND NEAR POINT CONCEPTION IS STILL SUFFICIENT TO SUSTAIN AN EDDY SO EVEN IF THIS EDDY DISSIPATES...ANOTHER EDDY WILL LIKELY DEVELOP OVERNIGHT TONIGHT. MARINE LAYER REMAINS FAIRLY DEEP OVER OUR CWFA BUT IT IS DOWN ABOUT 500 FEET FROM SUNDAY MORNING BASED ON NKX AND ACARS SOUNDINGS PLUS RECENT PILOT REPORTS OF TOPS. TOP REPORT OF 5000 FEET OUT OF KSNA APPEARS TO BE ASSOCIATED WITH A CONVERGENCE BAND ALONG THE ORANGE COUNTY COAST. PILOT REPORTS OUT OF KCRQ PUTS TOPS IN THAT AREA AROUND 4000 FEET WHILE ANOTHER REPORT OUT OF KMYF PUTS TOPS IN THE SAN DIEGO AREA AROUND 3500 FEET. CLOUDS ARE BEGINNING TO SHOW MORE BREAKS INLAND COMPARED WITH SUNDAY MORNING. THE EARLIER IDEA OF MORE CLEARING TODAY OVER SUNDAY APPEARS TO BE ON TRACK. 12Z ETA AND NGM BRING A S/WV RIDGE TO THE COAST TODAY AND TUESDAY WITH RISING HEIGHTS AND THICKNESS. THE ETA ALSO SUGGEST A WEAK OFFSHORE FLOW INTO THE INLAND EMPIRE AND THE LA BASIN AREA BUT THE FLOW WILL REMAIN ONSHORE ALONG THE SAN DIEGO COAST. THE COMBINATION OF RISING THICKNESS...INCREASED SUBSIDANCE...AND THE WEAK OFFSHORE FLOW WILL BRING WARMING MOST AREAS LATER THIS AFTERNOON WITH FURTHER WARMING ON TUESDAY. CURRENT FORECAST LOOKS TO BE ON TRACK SO NO UPDATES PLANNED AT THIS TIME. MRF STILL WANTS TO DEVELOP AN OMEGA BLOCK OVER THE GULF OF ALASKA LATER THIS WEEK WITH THE EASTERN ANCHOR LOW OVER THE PACIFIC NORTHWEST OR A LITTLE FURTHER SOUTH INTO NORTHERN CALIFORNIA OR NEVADA...STILL MUCH FURTHER NORTH THAN THE BLOCK TOWARDS THE END OF APRIL. LOCATION OF THE EASTERN ANCHOR LOW WILL STILL ALLOW MINOR S/WVS TO BRUSH BY SOUTHERN CALIFORNIA MAINTAINING THE ONSHORE FLOW WITH COASTAL EDDIES...AND WIND IN THE MOUNTAINS AND NORTHERN DESERTS. OTHERWISE CONTINUED DRY. SAN 000 .SAN...NONE. HORTON
FXUS66 KEKA 101537 ca AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 1100 AM EDT MON MAY 10 1999 SFC HIGH PRES REMAINS LOCKED OVER MI THIS MORNING...WITH THE UPPER LEVEL RIDGE AXIS EXTENDING NW FROM KY AND TN THROUGH NRN IL INTO NRN MN. STRONG CONVECTION CONTINUES TO FIRE JUST W OF THE RIDGE AXIS... WITH DEBRIS CLOUD SPILLING OVER THE RIDGE INTO LAKE SUPERIOR AND UPR MI. DEBRIS CLOUD CONSISTS OF FAIRLY THICK CI AND AC...BUT IS TENDING TO THIN WITH EASTWARD PROGRESSION AS IT RUNS INTO DRIER UPPER LEVEL AIR. LATEST RUC MOISTURE PROFILES SHOW THIS ENHANCED MOISTURE WITHIN A 700-500 MB LAYER. IN LOOKING AT A RUC CROSS SECTION...RH WITHIN THIS LAYER DOES INCREASE FROM AROUND 70 PCT TO 80-90 PCT THIS AFTERNOON OVER ERN UPR MI. PLAN VIEW CONFIRMS THAT ALL OF ERN UPR MI WILL LIKELY SEE AN INCREASE IN MID/UPPER LEVEL CLOUDINESS AS THE AFTERNOON PROGRESSES. FAR NRN LOWER MI MAY ALSO SEE SOME INCREASE IN MID/HIGH CLOUD BY 18Z. CURRENT OBS AND LATEST VSBL FROM ERN UPR MI SHOW SKC ACROSS THE AREA...BUT EXPECT CLOUDS WILL INCREASE AGAIN IN THE AFTERNOON WITH MORE CLOUDS IN SIGHT UPSTREAM AND CONSIDERING THE EXPECTED INCREASE IN MID/UPPER LEVEL MOISTURE JUST BEFORE 18Z. THUS WILL MAINTAIN A PARTLY SUNNY FORECAST FOR ERN UPR MI. WILL CONTINUE MOSTLY SUNNY FOR FAR NRN ZONES...BUT WILL GO WITH FULL SUN FOR THE REST OF NRN LOWER MI...AS ANY CI THAT MOVES THROUGH THIS REGION WILL LIKELY BE TOO THIN TO FILTER THE SUN. LATEST RUC MODEL SOUNDINGS INDICATE SLIGHTLY DEEPER MIXING POSSIBLE TODAY (THROUGH 850 MB VS. 900 MB YESTERDAY). HOWEVER...STRONG INVERSION ABOVE 850 WILL INHIBIT ANY MIXING OF WARMER AIR AND HIGHER WINDS DOWN TO THE SFC THIS AFTERNOON. FWC TEMPS ARE TOO WARM. ZONES HAVE ALREADY REFLECT A CUT IN GUIDANCE...AND APPEARS TO BE IN LINE WITH THE ABOVE CONSIDERATIONS AND WITH CURRENT TRENDS. NO CHANGES NEEDED TO TEMP FORECAST AT THIS TIME. .APX...NONE. EME
FXUS63 KAPX 100832 mi STATE FORECAST DISCUSSION NATIONAL WEATHER SERVICE ALBUQUERQUE NM 1125 AM MDT MON MAY 10 1999 QUICK AM UPDATE TO TWEAK WINDS A BIT AND MULL OVER THE COLD FRONT LURKING NEAR NE NM. WSHFT AT KCAO EARLIER WITH DEWPOINTS COMING UP ABOUT 18 DEGREES F IN 2 HOURS ON A NORTH WIND. WINDS HAVE SINCE BACKED TO THE NORTHWEST AND ITS BEGINNING TO WARM/DRY THERE AGAIN. AGREE WITH FWC...RUC AND 12Z ETA THAT WINDS IN THE NE WILL LIKELY BACK AROUND TO THE WEST THROUGH THE DAY...AS IS EVIDENT WITH PRETTY DECENT W WINDS AT THE MOMENT UPSTREAM AT KRTN AND KLVS. THIS SAME COLD FRONT WILL BE MY FORECAST PROBLEM FOR THE AFTERNOON PACKAGE. IT LOOKS LIKE IT WILL PLUNGE SOUTHWARD TONIGHT AND SET UP AN EASTERLY FLOW ACROSS MUCH OF ERN BORDER AREA BY MORNING...JUST IN TIME FOR A STRONGER VORT MAX TO MOVE EAST ACROSS THE AREA ON TUE. CSM .ABQ...NONE
FXUS75 KABQ 100844 nm AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY NATIONAL WEATHER SERVICE RAPID CITY SD 1025 AM MDT MON MAY 10 1999 THE 16Z SURFACE ANALYSIS SHOWED A TROUGH FROM EASTERN ND TO CENTRAL KS. A LOW WAS OVER EASTERN SD AND IN NORTH CENTRAL KS. WATER VAPOUR LOOP SHOWED UPPER CIRCULATION OVER WY. SEVERAL JET STREAKS ROTATING AROUND SYSTEM CAUSING BAND OF SHRA OVER MOST OF THE CWA. SOME SHSN UP IN THE HILLS WHERE COLD POOL ALOFT WAS PARKED. MAIN CONCERN THIS MORNING IS TEMPERATURES. THE 12Z RUC2 SUPPORTS LOWER TEMPERATURES THAN CURRENTLY FORECAST FOR AREAS UNDER RAIN. THIS MAKES SENSE GIVEN COLD AIR ADVECTION AND PRECIPITATION SEEN ON KUDX CWA. UPDATE WILL FOCUS ON TEMPERATURES WITH REST OF FORECAST LOOKING GOOD. THINK TSRA WILL BE EAST OF CWA THIS AFTERNOON...BUT WILL LEAVE MENTION IN SOUTH CENTRAL SD AS SHORTWAVE ON WATER VAPOUR ENTERING THE NEBRASKA PANHANDLE LOOKING MEATY AT THE MOMENT. .UNR...NONE. HELGESON
FXUS63 KABR 101547 sd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 1045 AM CDT MON MAY 10 1999 12Z RUC KEEPS DRY AIR FROM ABOUT 600 MB AND UP ACROSS FORECAST AREA...WHILE LOW LEVEL MOISTURE ALSO VERY SLOW TO PUSH INTO EASTERN MN. LATEST 88-D IMAGERY HAS CURRENT SHOWER/THUNDERSTORM ACTIVITY MOVING NEARLY DUE NORTH ACROSS MN...WITH LITTLE IF ANY EASTWARD MOVEMENT. 500 MB RIDGE HOLDING THE TROUGH BACK...WHICH WILL THEREFORE HOLD OFF THE AREA/S RAIN CHANCES. WILL UPDATE THE ZONES TO REMOVE RAIN CHANCES FOR THIS AFTERNOON. WILL ALSO BUMP TEMPERATURES UP FOR SOME ZONES...BASED ON CURRENT READINGS. .LSE...NONE. RIECK
FXUS63 KGRB 101048 wi