Severe Thunderstorm Warning 191, NWS Louisville, KY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
143 PM EDT MON JUL 22 2002

OK SO JUST MAYBE I WONT HAVE TO H2O THE LAWN IF THIS FCST PANS OUT.
SCT TS DEVELOPING WITHIN 310K UPGLIDE AND SFC MASS CONVERGENCE
REGIME COLOCATED WITH PWATS AOA 2 AND LIS EVEN DOWN TO -9C.
SYNOPTIC PICTURE SHOWS STRONG MID-LEVEL WAVE ROTATING THRU SRN
CANADA, PUSHING SFC TROF NOW OVER MID-MS RIVER VALLEY EVER SO SLOWLY
TO THE SE. PER 12Z LMK-MM5 THESE CURR STORMS SHOULD LAST INTO EARLY
EVENING, BEFORE BEING SUBDUED BY COMBINATION OF DAYTIME HEATING
LOSS, SOME PRE-FRONTAL SUBSIDENCE, AND SLIGHT DRYING OF PWATS (NOT
TO DEATH VALLEY LEVELS, BUT BELOW 2).

IN ASSOC WITH DECENT 700-500MB L/RS, A GOOD BET TS WILL DEVELOP
ALONG SFC TROF THRU EVENING, AS IT PUSHES SEWD TOWARDS CWA IN
RESPONSE TO FORCING FROM SRN CANADA WAVE. BOTH META/AVN DEVELOP
PERSISTENT SFC WAVE FEATURE ALONG TROF OVER SRN IL/WRN KY AFTER
MIDNIGHT, LIKELY IN RESPONSE TO CONVECTIVE DEVELOPMENT AND SECONDARY
500MB WAVE OVER SRN IA. THIS ALONG WITH DISTANCING OF SRN CANADA
WAVE FROM ATTENDANT FRONT AFTER 6Z/TUE WOULD SUGGEST A SLOWDOWN IN
SWD FRONTAL MVMT WITH TIME. HOWEVER IF TS NOT AS WIDESPREAD OVER
IL/MO THEN THIS SFC LOW FEATURE MAY NOT DEVELOP AS VIGOROUSLY, SO
FRONT MAY KEEP A STEADY SEWD PROGRESS OVERNIGHT. OVERALL, WILL GO
WITH AVN/META AND DEVELOP SFC WAVE, AND WILL KEEP LIKELY TS TOWARDS
DAWN IN SRN IND, WITH CHC TS NEAR SDF AND ELSEWHERE DRY (SAVE SCT
EVE TS). WITH SFC MOISTURE FROM AFT TS AND SOME CLOUD COVER COULD BE
A FAIRLY MUGGY NIGHT, ESPECIALLY IN THE URBAN AREAS, AS LOWS MAY
DROP ONLY INTO MIDDLE 70S.

THEN ON TUE IN RESPONSE TO WEAKENING FORCING ALOFT, SFC FRONT
BASICALLY DISINTEGRATES OVER CWA LEAVING L/V PBL FLOW OVERLAID WITH
POOL OF 850MB TDS APPROACHING 15C. BELIEVE SDF AND SRN IND AREAS
HAVE BEST SHOT FOR TS, AS BEST INGREDIENTS SET UP SHOP THERE. HEAVY
RAIN POTENTIAL SEEMS ACCEPTABLE WITH HIGH LOW-LEVEL TDS AND VERY
WEAK STEERING FLOW. OTHER LOCATIONS WILL GO WITH 50% CHC, INLINE
WITH ETA-MOS TRENDS.

LIGHT NELY SFC FLOW DEVELOPS FROM N TO S AS SFC HIGH GRAZES NERN US.
WILL PROBABLY SEE SOME ISO/SCT TS OVER MOST OF CWA TUE EVENING, THEN
MORE DIURNAL TS OVER CEN/SRN KY ON WED AS BEST 850-500MB MOISTURE
HEADS THAT WAY.

SDF...NONE.

SMALLCOMB

INZ076>079-083-084-089>092-KYZ023>043-045>049-053>057-061>067-
070>078-081-082-222200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LOUISVILLE KY
1200 PM EDT MON JUL 22 2002

...HEAT INDICES FROM 100 TO 105 DEGREES THIS AFTERNOON...

HIGH TEMPERATURES THIS AFTERNOON WILL RANGE FROM THE LOWER TO MIDDLE
90S ACROSS SOUTHERN INDIANA AND CENTRAL KENTUCKY. WHEN COMBINED WITH
THE HUMIDITY, HEAT INDICES WILL GENERALLY RANGE FROM 100 TO 105
DEGREES WITH SOMEWHAT WORSE CONDITIONS NEAR CONCENTRATED AMOUNTS OF
CONCRETE AND ASPHALT. SCATTERED THUNDERSTORMS ARE EXPECTED THROUGH
THE AFTERNOON, WHICH WOULD PROVIDE RELIEF TO SOME AREAS.

THE HEAT INDEX OR APPARENT TEMPERATURE IS A MEASURE OF THE EFFECT OF
HUMIDITY AND TEMPERATURE ON THE BODY. VALUES ABOVE 105 DEGREES CAN
CAUSE HEAT EXHAUSTION, SYMPTOMS OF WHICH ARE DIZZINESS AND NAUSEA.

PEOPLE WHO ARE SENSITIVE TO THE HEAT AS WELL AS THOSE WHO PLAN TO
ENGAGE IN STRENUOUS ACTIVITIES SHOULD TAKE THE NECESSARY PRECAUTIONS
OF DRINKING PLENTY OF WATER AND SEEKING FREQUENT BREAKS FROM THE
HEAT WHEN NECESSARY. IN ADDITION, GENEROUS AMOUNTS OF SUNSCREEN
SHOULD BE APPLIED AS THE ULTRAVIOLET INDEX WILL BE IN THE HIGH
CATEGORY TODAY.

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