Area Forecast Discussion
Issued by NWS Louisville, KY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KLMK 051054
AFDLMK

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
654 AM EDT WED AUG 5 2015

...UPDATED AVIATION DISCUSSION...

.SHORT TERM (NOW THROUGH THURSDAY)...
ISSUED AT 325 AM EDT WED AUG 5 2015

...FLASH FLOOD WATCH THIS AFTERNOON THROUGH EARLY FRIDAY...

A VERY WET SETUP LOOKS TO BE IN STORE FOR THE NEXT 24-48 HRS OVER
THE OHIO VALLEY FEATURING MULTIPLE ROUNDS OF SHOWERS/STORMS THAT
COULD POTENTIALLY LEAD TO FLOODING ISSUES.  INITIALLY FLASH FLOOD
GUIDANCE IS LOWEST EAST OF I-65 AND PARTICULARLY IN THE NORTHERN
BLUEGRASS REGION OF KY WHERE 1 HR FFG IS DOWN TO 1-1.6 INCHES.  THIS
AREA WILL BE SUSCEPTIBLE TO FLOODING PROBLEMS WITH THE FIRST ROUND
OF SHOWERS/STORMS.  HOWEVER, THE REST OF THE AREA LOOKS TO QUICKLY
BECOME AT RISK AS MULTIPLE BANDS OF CONVECTION CONTAINING VERY HEAVY
RAINFALL PUSH THROUGH THE OHIO VALLEY STARTING THIS AFTERNOON.

A FEW MODELS ARE STILL INDICATING SOME LIGHT DEVELOPMENT AROUND
SUNRISE ON THE NOSE OF A DECENT LLJ MAINLY WEST OF I-65. THE LATEST
HIGH-RES GUIDANCE DOES NOT SHOW MORNING CONVECTION SO CONFIDENCE IS
LOW IN IT OCCURRING AND EVEN IF IT DOES, IT LOOKS TO AFFECT AREAS
THAT CAN STILL HANDLE A BIT OF WATER BEFORE THEY EXPERIENCE FLOODING
ISSUES.

MODELS ARE IN AGREEMENT THAT THE FIRST NOTABLE ROUND OF
SHOWERS/STORMS AHEAD OF AN APPROACHING UPPER LEVEL TROUGH AND WEAK
SFC LOW WILL MOVE INTO OUR REGION BY EARLY TO MID AFTERNOON WITH THE
STRONGEST CONVECTION CLOSE TO A DIFFUSE BOUNDARY OVER SOUTH CENTRAL
KY.  A GOOD LLJ AS WELL AS FORCING FROM THE SLOW MOVING UPPER TROUGH
AND WEAK SFC LOW WILL CAUSE ROUNDS OF SHOWERS/STORMS TO CONTINUE
TONIGHT AND MUCH OF THE DAY THURSDAY BEFORE FINALLY MOVING OUT THURS
NIGHT.  PRECIPITABLE WATER AMOUNTS WILL RISE TO OVER 2 INCHES
TONIGHT WITH SOUNDINGS INDICATING A DEEP WARM CLOUD LAYER THROUGH
THURS EVENING RESULTING IN VERY EFFICIENT PRECIP PRODUCERS.  HIGH-
RES MODELS INDICATE REPEATED ROUNDS OF STORMS IN THIS VERY MOIST
ENVIRONMENT COULD RESULT IN BANDS OF VERY HEAVY RAINFALL AND THOSE
UNDER THESE BANDS COULD EXPERIENCE FLASH FLOODING. THOSE WHO LIVE
NEAR FLOOD PRONE AREAS SHOULD PAY PARTICULAR ATTENTION TO WEATHER
ALERTS AND WATER LEVELS OVER THE NEXT FEW DAYS.  TOTAL RAINFALL FOR
THE NEXT FEW DAYS SHOULD RANGE FROM 1 TO 3 INCHES WITH LOCALLY
HIGHER AMOUNTS POSSIBLE.

TEMPERATURES SHOULD TOP OUT IN THE MID TO UPPER 80S FOR HIGHS TODAY.
LOWS TONIGHT WILL HOLD IN THE UPPER 60S AND LOWER 70S.  A SLIGHTLY
COOLER AIRMASS ASSOCIATED WITH THE UPPER TROUGH AS WELL AS
CLOUDS/RAIN SHOULD LIMIT THURSDAY`S HIGHS TO THE UPPER 70S/LOWER 80S.

.LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)...
ISSUED AT 250 AM EDT WED AUG 5 2015

BY THURSDAY NIGHT...THE MAIN MID-LEVEL SHORTWAVE TROUGH WILL BE
ACROSS EASTERN KENTUCKY AND ASSOCIATED SHOWERS/STORMS ARE EXPECTED
TO BE PUSHING EAST. THE TREND WILL BE FOR DIMINISHING PRECIPITATION
CHANCES...ENDING TOWARD MIDNIGHT. UPPER LEVEL RIDGING ARRIVES IN ITS
WAKE...SETTING UP A DRY AND MORE PLEASANT PERIOD FROM FRIDAY THROUGH
SATURDAY AFTERNOON.

BY LATE SATURDAY THROUGH EARLY NEXT WEEK THE UPPER LEVEL PATTERN
THAT HAS BECOME NORMAL LATELY AROUND THE OH VALLEY WILL REASSERT
ITSELF...WITH A RIDGE OVER SOUTHWEST US / TEXAS AND A TROUGH OVER
THE GREAT LAKES. WEAK RIDGING / ZONAL FLOW LIES IN BETWEEN ACROSS
THE CENTRAL PLAINS INTO THE OH/TN VALLEYS WITH PERIODIC MID LEVEL
SHORTWAVES COMING THROUGH. CHANCES FOR STORMS WILL BEGIN TO RAMP
SOME ON SUNDAY BUT ESPECIALLY INTO NEXT WEEK AS THE FORECAST MODELS
SHOW THE POTENTIAL FOR SOME VIGOROUS WAVES TO DROP DOWN.

AS FAR AS SENSIBLE WEATHER AND IMPACTS...IT COULD BE AN UNSETTLED
PERIOD EARLY NEXT WEEK WITH A FEW ROUNDS OF STORMS. IF TIMING PLAYS
OUT...PEAK HEATING AND AN UPPER LEVEL TRIGGER COULD MAKE FOR SOME
STRONGER STORMS /GUSTY WINDS/ BUT THE MAIN STORY LOOKS TO BE HEAVY
RAINFALL.

SOME SIGNALS THAT A FRONT MIGHT MAKE IT THROUGH THE AREA DURING THE
MIDDLE OR LATTER PORTIONS OF NEXT WEEK WITH A COOLER AND DRIER HIGH
PRESSURE SYSTEM BUILDING IN FROM THE NORTHWEST. CONFIDENCE THAT FAR
OUT IS RATHER LOW...BUT WILL TREND PRECIPITATION CHANCES BELOW 20
PERCENT FOR NOW.

AS FAR AS TEMPERATURES GO...MORE OR LESS RIGHT AROUND NORMAL. THERE
ISN`T MUCH OF A SIGNAL FOR A STRONG PUSH OF HOT OR COOL AIR...SO THE
MODEL CONSENSUS OF HIGHS IN THE MID 80S TO NEAR 90 LOOKS GOOD AT
THIS POINT. SOME COOLER LOWS POSSIBLE THIS WEEKEND /LOW TO MID 60S/
BEFORE MOISTURE RAMPS UP BY SUNDAY. AT THAT POINT...LOWS NEXT WEEK
MAY ONLY DROP INTO THE UPPER 60S TO LOWER 70S.

&&

.AVIATION (12Z TAF UPDATE)...
ISSUED AT 650 AM EDT WED AUG 5 2015

THIS MORNING WE ARE IN A LULL IN BETWEEN WAVES OF CONVECTION. SOME
LIGHT BR HAS FORMED OVER THE AREA AND EXPECT IT TO PERSIST FOR
ANOTHER HOUR OR TWO BEFORE DISSIPATING.

MOST OF THE SHORT RANGE AND HIGH-RES MODELS INDICATE THAT SOME
MORNING SHOWERS/STORMS MAY STILL BE POSSIBLE AT THE TAF SITES SO
WILL MENTION WITH VCSH ATTM.  CONVECTION HAS REALLY BLOSSOMED OVER
SOUTHERN ILLINOIS WITHIN THE LAST HOUR BUT NOT SURE HOW FAR EAST IT
WILL MAKE IT.

A BETTER CHANCE FOR CONVECTION EXISTS LATER TODAY AS A SLOW MOVING
UPPER TROUGH AND WEAK SFC LOW PUSH EASTWARD ALONG A NEARLY
STATIONARY SFC BOUNDARY.  SHOWERS AND STORMS WILL BECOME LIKELY AS
THIS WEATHER SYSTEM MOVES INTO THE AREA LATER THIS
AFTERNOON/EVENING.

WINDS WILL BE LIGHT AND VARIABLE THROUGH THE MORNING HOURS.  THIS
AFTERNOON THEY WILL BECOME PREDOMINANTLY SW UNDER 7 KTS AND THEN
MORE EASTERLY TOWARD THE END OF THE TAF PERIOD AS THE WEATHER SYSTEM
DRAWS NEAR.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...FLASH FLOOD WATCH FROM 1 PM EDT /NOON CDT/ THIS AFTERNOON
     THROUGH LATE THURSDAY NIGHT FOR KYZ023>043-045>049-053>057-
     061>067-070>078-081-082.

IN...FLASH FLOOD WATCH FROM 1 PM EDT /NOON CDT/ THIS AFTERNOON
     THROUGH LATE THURSDAY NIGHT FOR INZ076>079-083-084-089>092.

&&

$$

SHORT TERM........AMS
LONG TERM.........ZBT
AVIATION..........AMS


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.