480
FXUS64 KHUN 220327
AFDHUN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1027 PM CDT SUN JUN 21 2026
..NEW NEAR TERM, SHORT TERM, LONG TERM
KEY MESSAGES
UPDATED AT 1026 PM CDT SUN JUN 21 2026
- CHANCES FOR SHOWERS AND THUNDERSTORMS WILL BEGIN TO INCREASE
BEFORE DAYBREAK, BUT WILL BE HIGHEST (85-95%) FROM LATE MONDAY
MORNING-EARLY MONDAY EVENING. CONDITIONS APPEAR FAVORABLE FOR
BOTH LOCALLY HEAVY RAINFALL/FLOODING AND STRONG-SEVERE STORMS,
WITH DAMAGING WINDS AND A FEW BRIEF TORNADOES THE MAIN CONCERN.
- AFTER A PERIOD OF DRIER CONDITIONS TUESDAY/TUESDAY NIGHT,
CHANCES FOR SHOWERS AND STORMS INCREASE TO 40-60% FROM
WEDNESDAY INTO THURSDAY. RAIN CHANCES WILL GRADUALLY DECREASE
FROM FRIDAY-SUNDAY.
NEAR TERM
(THIS EVENING THROUGH MONDAY)
ISSUED AT 1026 PM CDT SUN JUN 21 2026
ISOLATED OUTFLOW-DRIVEN SHOWERS AND THUNDERSTORMS WHICH BRIEFLY
SURVIVED AS THEY ENTERED THE SOUTHWESTERN PORTION OF THE CWFA
EARLIER THIS EVENING HAVE DISSIPATED WITH THE ONSET OF NOCTURNAL
COOLING. THUS, FOR THE REMAINDER OF THE EVENING, WE EXPECT WARM
AND DRY CONDITIONS TO EXIST AS A MODERATELY STRONG SSW WINDS AND
A BROKEN CIRRUS CANOPY WILL KEEP TEMPERATURES IN THE M-U 70S.
WELL TO OUR NORTHWEST, CLUSTERS OF THUNDERSTORMS WILL CONTINUE TO
EVOLVE FROM THE LOWER OH VALLEY SOUTHWESTWARD INTO CENTRAL OK AND
IN THE VICINITY OF A COLD FRONT TRAILING SOUTHWESTWARD FROM AN
AREA OF LOW PRESSURE THAT WILL TRAVEL EASTWARD FROM WEST-CENTRAL
IL INTO WESTERN OH BY 12Z. AS AN INITIALLY WEAK SOUTHWESTERLY LOW-
LEVEL JET BEGINS TO STRENGTHEN INTO THE 25-35 KNOT RANGE LATER
THIS EVENING, PATCHES OF LOW STRATUS CLOUDS WILL SPREAD
NORTHEASTWARD AFTER MIDNIGHT AND DEVELOPMENT OF A FEW SHOWERS AND
THUNDERSTORMS MAY OCCUR BETWEEN 8-12Z WITHIN THE LOW-LEVEL WAA
REGIME. THIS ACTIVITY WILL BE LOCATED AHEAD OF A CONGLOMERATE
CONVECTIVE OUTFLOW BOUNDARY (FROM WIDESPREAD CONVECTION TO OUR
NORTHWEST), WHICH SHOULD EXTEND FROM THE ARKALTEX NORTHEASTWARD
THROUGH WESTERN TN/EASTERN KY AND INTO THE CENTRAL APPALACHIANS
AT 12Z. ALTHOUGH COVERAGE OF CONVECTIVE CELLS WILL BE RATHER
DISPERSED AND CAPE WILL BE NEAR ITS MINIMUM VALUE FOR THE DAY (AS
WELL AS CINH NEAR IT MAXIMUM), 0-3KM SHEAR WILL PEAK BETWEEN
10-14Z AND MAY SUPPORT TRANSIENT MESOCYCLONES WITH ANY SUSTAINED
UPDRAFTS. THUS, CONDITIONS APPEAR CONDUCIVE FOR STRONG WIND GUSTS
UP TO 50-60 MPH AND PERHAPS A BRIEF TORNADO IN ADDITION TO
FREQUENT LIGHTNING.
OVER THE COURSE OF THE LATE MORNING PERIOD, TEMPS WILL BEGIN TO
WARM BACK INTO THE L-M 80S AND DIURNAL REINTENSIFICATION OF THE
OVERNIGHT MCS IS PREDICTED TO OCCUR FROM NORTHERN PORTIONS OF THE
ARKLAMISS NORTHEASTWARD INTO MIDDLE TN. BOTH GLOBAL MODELS AND
CAMS SUGGEST THAT THIS SYSTEM WILL TRACK EAST-SOUTHEASTWARD ACROSS
OUR REGION (FEATURING A SIMILAR RISK FOR STRONG WIND GUSTS AND
BRIEF TORNADOES COMPARED TO EARLY MORNING ACTIVITY), BUT MAY
BEGIN TO WEAKEN AS IT EXITS THE FORECAST AREA EARLY TOMORROW
AFTERNOON. IN THE WAKE OF LATE MORNING PRECIPITATION, RAPID
REDEVELOPMENT OF CONVECTION WILL LIKELY TAKE PLACE IN THE 20-22Z
TIMEFRAME ACROSS PARTS OF NORTHERN MS/NORTHWEST AL AND SOUTHERN
MIDDLE TN (IN THE VICINITY OF A TRAILING OUTFLOW BOUNDARY) AS AN
MCV RELATED TO OVERNIGHT STORMS ACROSS EASTERN OK/WESTERN AR
BEGINS TO APPROACH FROM THE WEST. ALTHOUGH THE LOW-LEVEL JET WILL
BE ON A WEAKENING TREND (REDUCING CONCERN FOR TORNADOES), MID-
LEVEL WINDS WILL QUICKLY STRENGTHEN AS THE MCV APPROACHES AND THIS
COULD SUPPORT UPSCALE DEVELOPMENT INTO 1-2 SMALL BOW ECHOES,
LEADING TO AN ENHANCED THREAT FOR DAMAGING STRAIGHT LINE WINDS UP
TO 65 MPH. IN ADDITION TO THE SEVERE RISK, PWAT VALUES IN THE
1.9-2.1" RANGE WILL YIELD EXCESSIVE RAINFALL RATES, WITH
URBAN/SMALL STREAM AND FLASH FLOODING BOTH A CONCERN.
SHORT TERM
(MONDAY NIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 1026 PM CDT SUN JUN 21 2026
PRESENT INDICATIONS ARE THAT A LOCALLY HIGHER RISK FOR DAMAGING
STRAIGHT LINE WINDS WILL CONTINUE FOR THE EASTERN PORTION OF THE
CWFA EARLY MONDAY EVENING, AS A MATURING MCS EXITS THE REGION TO
THE SOUTHEAST BETWEEN 0-3Z. IN THE WAKE OF THIS ACTIVITY, A COLD
FRONT WILL SHIFT SOUTHWARD, PERHAPS RESULTING IN DEVELOPMENT OF A
FEW ADDITIONAL SHOWERS THAT MAY PERSIST THROUGH MIDNIGHT BEFORE
DISSIPATING. LIGHT NORTHEAST WINDS IN THE WAKE OF THE FRONT WILL
ADVECT A DRIER, BUT HIGHLY MODIFIED CANADIAN AIRMASS SOUTHWESTWARD
INTO THE REGION, LEADING TO A TEMPORARY PERIOD OF RAIN-FREE
CONDITIONS FOR OUR NORTHEASTERN FORECAST ZONES FROM TUESDAY INTO
TUESDAY NIGHT. THESE CONDITIONS MAY VERY WELL EXIST REGION-WIDE,
BUT WITH NORMAL LEVELS OF UNCERTAINTY REGARDING PRECISELY WHERE
THE FRONT WILL BECOME STATIONARY, WE WILL MAINTAIN LOW-MEDIUM POPS
IN THE SOUTHWEST.
DURING THE TIMEFRAME FROM WEDNESDAY-WEDNESDAY NIGHT, MODELS
SUGGEST THAT THE FRONT WILL BEGIN TO TO LIFT NORTHEASTWARD ONCE
AGAIN IN RESPONSE TO A NORTHERN STREAM VORT MAX AND WEAK AREA OF
SURFACE LOW PRESSURE OVER THE WESTERN GREAT LAKES. A MOIST
AIRMASS WILL RETURN TO THE REGION AS THIS OCCURS, WITH COVERAGE OF
SHOWERS AND THUNDERSTORMS EXPECTED TO INCREASE FROM SW-TO-NE
DURING THE AFTERNOON AND EVENING HOURS. FORTUNATELY, DEEP-LAYER
SHEAR WILL BE MUCH WEAKER (COMPARED TO TOMORROW), REDUCING THE
THREAT FOR ORGANIZED/SEVERE CONVECTION. REGARDING TEMPERATURES,
DAYTIME HIGHS WILL REMAIN IN THE L-M 80S WITH OVERNIGHT LOWS IN
THE M-U 60S (L-M 60S ON TUESDAY NIGHT) .
LONG TERM
(THURSDAY THROUGH SUNDAY)
ISSUED AT V CDT SUN JUN 21 2026
WE CONTINUE IN A GENERALLY WET PATTERN THROUGH THE BEGINNING OF
THE LONG TERM PERIOD, WITH AT LEAST LOW CHANCES (30%) OF SHOWERS
AND THUNDERSTORMS DAILY. WITH HIGH PRESSURE OVER THE SOUTHEASTERN
US AND LOW PRESSURE OVER THE GREAT LAKES REGION, THE TN VALLEY
WILL REMAIN WEDGED BETWEEN WITH AN UPPER LEVEL SHORTWAVE FORECAST
TO PUSH EASTWARD INTO THE AREA BY THURSDAY INTO FRIDAY. AS THIS
OCCURS, RAINFALL CHANCES WILL INCREASE TO MEDIUM (40-60%) BOTH
THURSDAY AND FRIDAY AFTERNOONS WITH THE ASSISTANCE OF A LINGERING
FRONTAL BOUNDARY SOUTH OF THE AREA AS WELL AS SOUTHWESTERLY FLOW.
THERE REMAINS SOME MODEL DISAGREEMENT IN THE POTENTIAL ENVIRONMENT
BASED ON PLACEMENT/TRACK OF AFOREMENTIONED UPPER LEVEL SHORTWAVE,
HOWEVER, SOUTHWESTERLY FLOW WILL LIKELY CONTRIBUTE TO A MOIST
ENVIRONMENT WITH PWATS REACHING AROUND 1.7-1.8" (JUST BELOW 90TH
PERCENTILE SOUNDING CLIMATOLOGY PER BMX). THE MAJORITY OF
RAINFALL/FLASH FLOOD POTENTIAL WILL LIKELY REMAIN TO OUR WEST IN
AREAS WHERE THE WEATHER PREDICTION CENTER HAS ALREADY HIGHLIGHTED
IN A MARGINAL (RISK LEVEL 1 OF 4) OUTLOOK FOR EXCESSIVE RAINFALL.
RAIN CHANCES WILL GRADUALLY DECREASE AS WE HEAD INTO THE WEEKEND
AS SFC HIGH PRESSURE BEGINS WORKING IN FROM THE WEST. HEAT WILL BE
A CONCERN TOWARDS THE END OF THE WEEK AS WELL AS HIGHS ARE
FORECAST TO REACH THE UPPER 80S TO LOW 90S WITH HEAT INDEX VALUES
AROUND 100 DEGREES BY SATURDAY AND SUNDAY. IF YOU HAVE OUTDOOR
INTERESTS AT THE END OF THE WORK WEEK, BE SURE TO CHECK BACK IN
FOR UPDATES.
AVIATION
(00Z TAFS)
ISSUED AT 728 PM CDT SUN JUN 21 2026
VFR CONDITIONS WILL CONTINUE AT THE HSV/MSL TERMINALS THIS
EVENING, AS A BKN-OVC LAYER OF CONVECTIVE DEBRIS CLOUDS SPREADS
NORTHEASTWARD. ALTHOUGH A 5-10 KT SW WIND IN THE LOW-LEVELS WILL
KEEP THE BOUNDARY LAYER WELL-MIXED (AND REDUCE CONCERN FOR BR/FG
DEVELOPMENT), A SOUTHWESTERLY LOW-LEVEL JET WILL PROGRESSIVELY
STRENGTHEN THROUGHOUT THE NIGHT AS A SFC LOW TRACKS EASTWARD
ACROSS IL/IN/OH. THIS WILL RESULT IN FORMATION OF AN INITIALLY
SCATTERED LAYER OF STRATOCU BY 6Z, WHICH SHOULD TRANSITION INTO A
BROKEN LAYER OF MVFR STRATUS BY 10Z (THAT WILL LARGELY REMAIN
INTACT THRU THE END OF THE TAF PERIOD). CHANCES FOR SHRA/TSRA WILL
BEGIN TO INCREASE SHORTLY AFTER MIDNIGHT, AS THE LOW-LEVEL
STRENGTHENS AHEAD OF AN APPROACHING MCS. HOWEVER, THIS ACTIVITY
SHOULD REMAIN SUFFICIENTLY SCATTERED AND WE WILL NOT MENTION IN
THE FORECAST ATTM. GREATER IMPACTS FROM THE MCS WILL LIKELY COME
FROM 10-16Z, AT WHICH POINT MVFR VSBY REDUCTIONS IN HVY RAIN AND
AWWS FOR LIGHTNING AND STRONG WIND GUSTS IN EXCESS OF 35-45 KNOTS
CAN BE EXPECTED. AS THE MORNING MCS SPREADS SOUTHEASTWARD AND OUT
OF THE REGION BY EARLY-MID AFTN, CONVECTION MAY REDEVELOP ACROSS
PARTS OF NW AL/SOUTHERN MIDDLE TN LATE IN THE TAF PERIOD AND
ADDITIONAL PROB30 GROUPS WILL BE INCLUDED IN THE NEXT ISSUANCE OF
THE TAFS.
HUN WATCHES/WARNINGS/ADVISORIES
AL...NONE.
TN...NONE.
NEAR TERM...70/DD
SHORT TERM....70/DD
LONG TERM....HC
AVIATION...70
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