000 NOUS44 KHGX 272255 PNSHGX TXZ163-164-176>179-195>200-210>214-226-227-235>238-281100- PUBLIC INFORMATION STATEMENT NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 555 PM CDT WED JUN 27 2007 ...JUNE 24-30, 2007 IS LIGHTNING AWARENESS WEEK... THE WEEK OF JUNE 24TH THROUGH JUNE 30TH IS LIGHTNING AWARENESS WEEK NATIONWIDE. HERE IN TEXAS...25 PEOPLE HAVE LOST THEIR LIVES DUE TO LIGHTNING OVER THE PAST 10 YEARS. LIGHTNING IS CAUSED BY THE INTERACTION OF SUPERCOOLED WATER AND ICE CRYSTALS OF DIFFERENT SIZES. THE SMALLER AND HIGHER ALTITUDE ICE CRYSTALS TEND TO CREATE POSITIVE CHARGE WHILE NEGATIVE CHARGE IS BUILT UP ON THE LARGER ICE PARTICLES AT LOWER ALTITUDES. THIS CAUSES REGIONS OF POSITIVE AND NEGATIVE CHARGE IN THE STORM. WHEN THE ELECTRIC FIELDS BECOME STRONG ENOUGH...ELECTRICAL BREAKDOWN IN THE FORM OF LIGHTNING OCCURS. THERE ARE TWO PRIMARY MODES OF LIGHTNING. CLOUD TO GROUND LIGHTNING EXTENDS FROM A CLOUD TO THE SURFACE OF THE EARTH AND PRESENTS A HAZARD TO LIFE AND PROPERTY. INTRA CLOUD LIGHTNING OCCURS THREE TO FOUR TIMES MORE FREQUENTLY THAN CLOUD TO GROUND LIGHTNING...BUT PRESENTS A HAZARD PRIMARILY TO AVIATION. RESEARCH IS SHOWING THAT INTRA CLOUD LIGHTNING REVEALS USEFUL INSIGHT TO THE EVOLUTION OF THUNDERSTORMS INCLUDING SEVERE WEATHER. AS MOST LIGHTNING FATALITIES OCCUR WITH THE FIRST AND LAST FLASH OF A STORM ONE SHOULD USE CAUTION AROUND THUNDERSTORMS. WHEN OUTDOORS...IF YOU CAN HEAR THUNDER YOU ARE IN DANGER OF BEING STRUCK. HEAD INDOORS AND REMAIN INSIDE UNTIL 30 MINUTES AFTER THE LAST STRIKE. WHEN THUNDER ROARS...GO INDOORS. HERE ARE A FEW FACTS ABOUT LIGHTNING. THE VISIBLE LIGHTNING FLASH THAT PEOPLE SEE ALMOST ALWAYS PROPAGATES UPWARD FROM THE SURFACE TO THE CLOUD. IN SOUTHEAST TEXAS...MOST INTRA CLOUD LIGHTNING OCCURS NEAR THIRTY THOUSAND FEET. INTRA CLOUD LIGHTNING HAS BEEN KNOWN TO TRAVEL MORE THAN ONE HUNDRED MILES FROM ITS INITIATION POINT. IN SOUTHEAST TEXAS...THE HOUSTON NATIONAL WEATHER SERVICE OFFICE IS ONE OF A FEW OFFICES NATIONWIDE THAT RECEIVE REAL TIME THREE DIMENSIONAL LIGHTNING DATA THANKS TO RESEARCHERS AT TEXAS A & M UNIVERSITY. FORECASTERS USE THIS DATA AS YET ANOTHER TOOL TO HELP FORECASTERS WITH WARNING DECISIONS AND AVIATION FORECASTS. NEAR REAL TIME LIGHTNING MAPS FOR HOUSTON ARE ALSO AVAILABLE TO THE PUBLIC VIA THE INTERNET. SHOULD YOU HAVE QUESTIONS ABOUT LIGHTNING VISIT THE LIGHTNING SAFETY WEB PAGE AT HTTP://WWW.LIGHTNINGSAFETY.NOAA.GOV OR CONTACT YOUR HOUSTON GALVESTON NATIONAL WEATHER SERVICE OFFICE. $$