Area Forecast Discussion
Issued by NWS Huntsville, AL

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
FXUS64 KHUN 012300 AAA
AFDHUN

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE HUNTSVILLE AL
600 PM CDT SUN MAY 1 2016

.UPDATE...
FOR 00Z TAFS

&&

.DISCUSSION...
/ISSUED 317 PM CDT SUN MAY 1 2016/

LATEST WATER VAPOR IMAGERY SHOWS AN UPPER LOW OVER SOUTHERN IOWA
CLOSED OFF FROM THE MAIN UPPER LEVEL TROUGH EXTENDING OVER MUCH OF
THE WESTERN CONUS. AT THE SURFACE...THE ASSOCIATED LOW WAS SITUATED
OVER ILLINOIS...WITH A COLD FRONT TRAILING SOUTHEASTWARD INTO
LOUISIANA. ACROSS THE LOCAL AREA...CLOUDY SKIES WERE KEEPING TEMPS
IN THE UPPER 70S. ONGOING CONVECTION TO OUR SOUTH...THAT DEVELOPED
ALONG A WEAK BOUNDARY...HAS INCREASED IN COVERAGE OVER THE LAST
SEVERAL HOURS. WITH AN EAST...NORTHEAST MOVEMENT...THE PRECIP WILL
ENTER THE SOUTHERN PORTION OF THE AREA WITHIN THE NEXT HOUR OR
SO...HOWEVER NOT EXPECTING MUCH PROGRESSION NORTH OF THE TN RIVER.
MEANWHILE...CONVECTION HAS INCREASED ALONG THE FRONT OVER THE LAST
COUPLE OF HOURS. THE SLOW PROGRESSION OF THE FRONT WILL KEEP THIS
ACTIVITY FROM REACHING OUR AREA DURING THE OVERNIGHT HOURS...EVEN AS
IT OUTRUNS THE MAIN FRONT. IN FACT...LATEST SHORT TERM HIRES
GUIDANCE HAS MUCH OF THE ACTIVITY ALONG THE FRONT...AND TO OUR SOUTH
DISSIPATING BEFORE IT REACHES INTO N AL. GIVEN THIS...ALONG WITH
SOME UNCERTAINTY...HAVE MAINTAINED A LOW END CHANCE FOR
THUNDERSTORMS DURING THE EARLY EVENING HOURS.

THE COLD FRONT WILL SLOWLY PUSH EAST DURING THE OVERNIGHT
HOURS...AND MAY REACH OUR WESTERN ZONES JUST BEFORE DAYBREAK.
AS STATED ABOVE...CONVECTION ALONG THE FRONT MAY DIMINISH
OVERNIGHT...GIVEN THE LOSS OF DAYTIME HEATING AND THE LACK OF STRONG
VERTICAL FORCING ALONG THE FRONT. THERE MAY BE SCATTERED SHOWERS
DEVELOPING AS IT ENTERS N AL...HOWEVER GUIDANCE SUGGESTS THAT THE
COVERAGE ALONG THE FRONT WILL INCREASE THROUGHOUT THE DAY AS OUR
INSTABILITY INCREASES. A 60 KT UPPER LEVEL JET WILL SUPPORT MODEST
WIND SHEAR...AND WITH FORECAST INSTABILITY APPROACHING...IF NOT
EXCEEDING...1000 J/KG...THERE MAY BE A FEW ORGANIZED UPDRAFTS WITHIN
STORMS THAT DEVELOP ALONG THE FRONT. HOWEVER...THE WEAK NATURE OF
THE UPPER LEVEL SUPPORT AND FORECAST INSTABILITY/SHEAR...NOT
EXPECTING WIDESPREAD SEVERE THUNDERSTORMS.

THE FRONT WILL MOVE THROUGH THE AREA DURING THE OVERNIGHT HOURS ON
TUESDAY...WITH MUCH OF PRECIP COMING TO AN END BY DAYBREAK. THERE
MAY BE LINGERING SHOWERS ACROSS THE EAST...BUT ANYTHING SHOULD BE
ISOLATED. NORTHERLY WINDS WILL HELP FILTER IN DRY AIR BEHIND THE
FRONT...WITH FORECAST DEWPOINTS DROPPING INTO THE UPPER 40S BY
MIDWEEK. THE MAIN UPPER TROUGH WILL FINALLY SHIFT ACROSS THE AREA
DURING THE DAY ON WEDNESDAY...WITH A SLIGHT CHANCE OF SHOWERS ACROSS
OUR TN COUNTIES AS IT MOVES THROUGH. TEMPERATURES WILL REALLY BEGIN
TO COOL AS THIS TROUGH SHIFTS EAST...AND AMPLIFIED RIDGING BEGINS TO
BUILD INTO THE FORECAST AREA. THE COOLEST TEMPS WILL BE ON
THURSDAY...WITH MAX TEMPS FORECAST TO REMAIN IN THE UPPER 60S.
THINGS BEGIN TO WARM UP THROUGH THE WEEKEND...AS THE RIDGE CONTINUES
TO MOVE EASTWARD.

73

&&

.AVIATION...
FOR 00Z TAFS... ALTHOUGH A CHANCE OF SHRA/TSRA REMAINS THIS EVENING,
CONFIDENCE IS TOO LOW TO INCLUDE IN PREVAILING WX. THUS, HAVE GONE
WITH VCSH THROUGH TONIGHT, BUT MAINTAINED A TEMPO TSRA GROUP FROM
10-14Z AT KMSL AND 12-16Z AT KHSV WHEN REDEVELOPMENT IS EXPECTED.
CIGS OF ~020AGL ARE EXPECTED TO DEVELOP BY 05-07Z. SOME FOG IS PSBL,
AND WILL CONTINUE TO MONITOR THE THREAT OF THIS OCCURRING THIS
EVENING. SCT-NMRS SHRA/TSRA ARE ANTICIPATED ON MONDAY, BUT EXACT
TIMING AND COVERAGE IS STILL UNCERTAIN, SO OPTED FOR VCTS AT BOTH
KMSL AND KHSV.


&&

.HUN WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
TN...NONE.
&&

$$

FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE
AT WEATHER.GOV/HUNTSVILLE.


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