247
FXUS64 KHUN 021758
AFDHUN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1258 PM CDT SAT MAY 2 2026
..NEW AVIATION
KEY MESSAGES
UPDATED AT 1119 AM CDT SAT MAY 2 2026
- THERE IS A LOW CHANCE FOR SHOWERS LATE THIS AFTERNOON AND
EARLY THIS EVENING. A FEW INSTANCES OF WIND GUSTS UP TO 30-40
MPH AND PERHAPS SOME SMALL GRAUPEL MAY OCCUR WITH THE HEAVIER
SHOWERS.
- CONDITIONS WILL BECOME FAVORABLE FOR THE DEVELOPMENT OF FOG
BEGINNING LATE THIS EVENING (SOME OF WHICH COULD BECOME
WIDESPREAD AND DENSE EARLY SUNDAY MORNING). SPOTTY FROST MAY
ALSO DEVELOP IN ISOLATED COLD SPOTS ACROSS SOUTHERN
TN/NORTHEAST AL.
- THERE IS A LOW RISK FOR STRONG TO SEVERE STORMS ON WEDNESDAY.
NEAR TERM
(REST OF TODAY AND TONIGHT)
ISSUED AT 1119 AM CDT SAT MAY 2 2026
IN THE MID/UPPER-LEVELS, A DEEPENING COLD CORE VORTEX WILL LIFT
SLOWLY NORTHWARD ACROSS WESTERN QUEBEC TODAY AND TONIGHT. AN
INITIALLY POSITIVELY-TILTED LONGWAVE TROUGH AXIS ATTACHED TO THE
VORTEX IS EXPECTED TO SHIFT EAST-SOUTHEASTWARD ACROSS THE TN
VALLEY LATER THIS AFTERNOON, BEFORE TAKING ON A MORE NEUTRAL TILT
TONIGHT IN RESPONSE TO AN UPSTREAM SPEED MAX DIGGING SOUTHEASTWARD
ACROSS THE NORTHERN PLAINS AND UPPER MIDWEST. AT THE SURFACE, A
DEVELOPING AREA OF LOW PRESSURE ACROSS NORTH FL WILL ADVANCE
NORTHEASTWARD TO A POSITION OFF THE COAST OF NC BY LATE THIS
AFTERNOON, BEFORE DEEPENING MORE SUBSTANTIALLY OFF THE NORTHERN
MID-ATLANTIC COAST OVERNIGHT. ALTHOUGH THE PERIPHERAL STRATIFORM
RAIN SHIELD ON THE NORTHWESTERN FLANK OF THE LOW IS NOW WELL TO
OUR SOUTHEAST, AN OVERCAST ALTOSTRATUS LAYER (AND SOME PATCHES OF
VIRGA) IN ITS WAKE WILL PERSIST ACROSS EASTERN PORTIONS OF THE
CWFA FOR MUCH OF THE MORNING, LIMITING DIURNAL WARMING TO SOME
EXTENT.
THROUGHOUT THE LATE MORNING AND INTO THE AFTERNOON HOURS, WEAK
CONVECTION IS PREDICTED TO EXPAND IN COVERAGE FROM SOUTHERN IL
SOUTHEASTWARD THROUGH THE LOWER OH VALLEY AND INTO PORTIONS OF
WESTERN AND MIDDLE TN AS SYNOPTIC SCALE ASCENT STRENGTHENS
DOWNSTREAM FROM THE APPROACHING UPPER SPEED MAX. SOME OF THIS
ACTIVITY MAY INDEED REACH THE LOCAL FORECAST AREA BY MID-AFTERNOON
(20-21Z) AND PERSIST THROUGH ~2-3Z, AND WE HAVE MADE A SLIGHT
INCREASE IN POPS DURING THIS TIMEFRAME TO REFLECT LASTEST
SOLUTIONS FROM BOTH THE GLOBAL MODELS AND HIGHER-RESOLUTION CAMS.
A DEEP-WELL MIXED BOUNDARY LAYER (EXTENDING UP TO 6-10 KFT) IS
EVIDENT IN FORECAST SOUNDINGS, AND THIS COULD RESULT IN SOME
INSTANCES OF BRIEF WIND GUSTS UP TO 30-40 MPH AND PERHAPS EVEN A
FEW PELLETS OF GRAUPEL WITH ANY HIGHER REFLECTIVITY CORES, BUT
WITH TEMPS IN THE M-U 60S ONLY SUPPORTING CAPE UP TO 150-200 J/KG
THE RISK FOR LIGHTNING WILL BE VERY LOW. SKIES WILL QUICKLY CLEAR
BY LATE THIS EVENING AS THE CONVECTIVE REGIME DISSIPATES, AND WITH
A BROADENING SURFACE RIDGE EXPECTED TO LIE ACROSS THE REGION,
CONDITIONS WILL BE FAVORABLE FOR THE DEVELOPMENT OF FOG (SOME OF
WHICH COULD BECOME WIDESPREAD AND DENSE) AS TEMPERATURES FALL INTO
THE U30S-L40S. ALTHOUGH A FEW PATCHES OF FROST MAY ALSO OCCUR IN
ISOLATED COLDER SPOTS ACROSS SOUTHERN MIDDLE TN/NORTHEAST AL,
COVERAGE DOES NOT APPEAR HIGH ENOUGH TO WARRANT SPECIAL HEADLINES
AT THIS POINT.
SHORT TERM
(SUNDAY THROUGH MONDAY NIGHT)
ISSUED AT 1119 AM CDT SAT MAY 2 2026
DRY NORTHWEST FLOW ALOFT WILL PREVAIL ACROSS THE TN VALLEY ON
SUNDAY/SUNDAY NIGHT, AS OUR REGION WILL REMAIN UNDER THE INFLUENCE
OF A COLD CORE VORTEX IN THE PROCESS OF MAKING A CYCLONIC LOOP
ACROSS SOUTHEASTERN CANADA. AS THE AXIS OF A REMNANT SURFACE RIDGE
CONTINUES TO SHIFT SOUTHEASTWARD AND AWAY FROM THE REGION, LIGHT-
MODERATE SOUTHWESTERLY RETURN FLOW AND ABUNDANT SUNSHINE WILL
YIELD WARMER AFTERNOON HIGHS TOMORROW (U60S-L70S IN THE VALLEY),
FOLLOWED BY A SHARP GRADIENT IN LOW TEMPS MONDAY MORNING (L40S/NE
TO L50S/NW). ALTHOUGH UPSCALE GROWTH OF NOCTURNAL CONVECTIVE
CLUSTERS IS PREDICTED TO OCCUR ALONG AN AXIS FROM THE MO-VALLEY
INTO EASTERN KY SUNDAY EVENING (AS A WESTERLY LOW-LEVEL JET
STRENGTHENS IN ADVANCE OF A NORTHERN STREAM SHORTWAVE TROUGH
DIGGING INTO WESTERN ONTARIO), THIS ACTIVITY WILL REMAIN SAFELY
DISPLACED TO OUR NORTH AND DRY CONDITIONS WILL CONTINUE FOR THE
LOCAL AREA. DURING THE PERIOD FROM MONDAY INTO MONDAY NIGHT, MID-
LEVEL WINDS WILL BACK TO THE WEST-SOUTHWEST, WHICH ALONG WITH A
MODEST STRENGTHENING OF SOUTHWESTERLY FLOW IN THE LOW-LEVELS WILL
LEAD TO A CONTINUATION OF THE WARMING TREND, AS HIGHS RETURN TO
THE U70S-L80S MONDAY AND LOWS WARM INTO THE L-M 50S MONDAY NIGHT.
LONG TERM
(TUESDAY THROUGH FRIDAY)
ISSUED AT 952 PM CDT FRI MAY 1 2026
AN ANOMALOUS COLD PATTERN SHOULD CONTINUE ACROSS MUCH OF THE
NORTH AMERICAN DOMAIN, COURTESY OF A RATHER DEEP UPPER LOW
SITUATED OVER SOUTHERN ONTARIO AND QUEBEC. THE PRESENCE OF THIS
VORTEX HAS CREATED LOWER HEIGHTS ACROSS THE EASTERN CONUS, WITH
RESULTANT COOLER THAN NORMAL TEMPERATURES. BY THE TIME WE GET INTO
LATER MONDAY, LOWER THAN NORMAL MEAN UPPER HEIGHTS SHOULD BE
SITUATED OVER SOUTHERN ONTARIO. ANOTHER UPPER LEVEL SYSTEM
DEVELOPING WEST OF VANCOUVER WILL SLOWLY DEEPEN AS IT MOVES
SOUTHWARD ACROSS THE CENTRAL CALIFORNIA COAST ON MONDAY. IT WILL
EVENTUALLY BECOME PART OF A SYNOPTIC SCALE THROUGH THAT SHOULD
MOVE EASTWARD ACROSS THE LOWER-48 IN THE NEXT WORK WEEK.
THIS NEXT SYSTEM COULD PRODUCE HIGHER TERRAIN SNOW IN THE ROCKIES
EARLY NEXT WEEK, AS A SURFACE LOW DEVELOPS OVER THE FRONT RANGE
AND ADJACENT HIGH PLAINS. AS IT TRAVERSES MORE TO THE EAST, THIS
STORM SYSTEM WILL TAP MORE MOISTURE FROM THE GULF REGION. CLOSER
TO THIS REGION, SURFACE HIGH PRESSURE WILL MOVE EAST OF THE
TENNESSEE VALLEY ON MONDAY, INDUCING A SOUTHERLY FLOW AND ALSO
BRINGING DEEPER MOISTURE FROM THE GULF. AN ASSOCIATED COLD FRONT
NEARING FROM THE WEST WILL BRING AN INCREASE IN CLOUDS, ALONG WITH
CHANCES OF SHOWERS AND THUNDERSTORMS. GENERAL MODEL OUTPUT THIS
FAR OUT WAS SUGGESTING THAT SOME STORMS DURING WEDNESDAY AFTERNOON
AND NIGHT-TIME COULD BECOME STRONG TO SEVERE IN INTENSITY, ALONG
WITH LOCALLY HEAVY RAIN. THE UPPER TROUGH AS IT SWEEPS ACROSS THE
OHIO/TENNESSEE VALLEY REGION ALSO BECOME NEUTRALLY TILTED, WHICH
CAN HELP ENHANCE OVERALL STORM INTENSITY.
A COLD FRONT WITH THIS NEXT SYSTEM SHOULD MOVE ACROSS THE AREA ON
THURSDAY. GIVEN THE PRESENCE OF THE UPPER LEVEL VORTEX HANGING
TOUGH OVER THE HUDSON BAY, PRODUCING INHERENTLY LOWER HEIGHTS, AND
A NW-N SURFACE FLOW AS CANADIAN HIGH PRESSURE BUILDS OVER THE
REGION, WILL BRING MORE UNSEASONABLY COOL CONDITIONS TO CLOSE OUT
THE LATTER WORK WEEK.
FOR THE EXTENDED PERIOD, DAILY TEMPERATURES FOR THE START OF A
NEW WORKWEEK SHOULD BE A TAD MILDER, WITH LOWS SUNDAY NIGHT FROM
THE LOWER 40S EAST TO LOWER 50S WEST. HIGH TEMPERATURES IN THE
TUESDAY THROUGH WEDNESDAY PERIOD SHOULD RISEN INTO THE MID/UPPER
70S, A LITTLE COOLER THAN SEASONABLE NORMS OF AROUND 80. AFTER THE
FRONT PASSES THURSDAY, HIGHS THAT DAY SHOULD ONLY RISE INTO THE
LOWER 70S, AND IN THE LOW/MID 70S NEXT FRIDAY.
AVIATION
(18Z TAFS)
ISSUED AT 1258 PM CDT SAT MAY 2 2026
A DEEP, WELL-MIXED BOUNDARY LAYER WILL EXIST ACROSS THE REGION
TODAY, BENEATH COLD TEMPERATURES ALOFT. THIS SETUP WILL PROMOTE
DEVELOPMENT OF SCT-BKN HIGH-BASED CU CAPABLE OF PROVIDING
INTERMITTENT VFR CIGS IN THE 4-10 KFT LAYER. A FEW SHRA MAY ALSO
OCCUR INVOF THE TERMINALS (MAINLY BETWEEN 20-21Z AND 2-3Z) BUT DUE
TO LIMITED COVERAGE, WE HAVE NOT INCLUDED THIS IN THE OFFICIAL
FORECAST AT THIS POINT. HOWEVER, SHOULD A STRONGER SHOWER DIRECTLY
IMPACT EITHER HSV OR MSL, BRIEF WIND GUSTS OF 25-35 KNOTS AND
PERHAPS SOME PELLETS OF GRAUPEL COULD OCCUR. SKIES WILL BECOME
CLEAR LATE THIS EVENING, WITH LGT/VRBL-CALM WINDS SUPPORTING THE
DEVELOPMENT OF BR/FG EARLY SUN MORNING. ALTHOUGH THE EXTENT OF
VSBY REDUCTIONS IS UNCLEAR, A TEMPO GROUP HAS BEEN INCLUDED FROM
9-13Z TO ADDRESS THIS POTENTIAL IMPACT. VFR CONDITIONS AND A LGT
SW FLOW WILL RETURN BY THE END OF THE TAF PERIOD.
HUN WATCHES/WARNINGS/ADVISORIES
AL...NONE.
TN...NONE.
NEAR TERM...70/DD
SHORT TERM...70/DD
LONG TERM...RSB
AVIATION...70/DD
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