262
FXUS64 KHUN 020421
AFDHUN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1121 PM CDT WED JUL 1 2026
..NEW NEAR TERM, SHORT TERM, LONG TERM
KEY MESSAGES
UPDATED AT 1121 PM CDT WED JUL 1 2026
- AN EXTREME HEAT WARNING REMAINS IN EFFECT THROUGH 7 PM THURSDAY
DUE TO A COMBINATION OF AFTERNOON TEMPERATURES IN THE MID-
UPPER 90S AND HEAT INDICES OF 108-112F. A HEAT ADVISORY WILL
REMAIN IN EFFECT FROM 7 PM THURSDAY-7 PM FRIDAY.
- STRONG-SEVERE THUNDERSTORMS WILL IMPACT PORTIONS OF THE REGION
ONCE AGAIN ON THURSDAY AND FRIDAY (MAINLY FROM LATE AFTERNOON
INTO THE EVENING). THESE WILL FEATURE A RISK FOR LOCALLY
DAMAGING DOWNBURST WINDS, SMALL HAIL AND EXCESSIVE LIGHTNING.
- THE COVERAGE OF AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS
WILL BEGIN TO INCREASE THIS WEEKEND AND WILL REMAIN IN THE
40-60% RANGE THROUGH THE MIDDLE OF NEXT WEEK.
NEAR TERM
(THIS EVENING THROUGH THURSDAY)
ISSUED AT 1121 PM CDT WED JUL 1 2026
A STRONG 500-MB HIGH WILL REMAIN POSITIONED ACROSS THE CENTRAL
APPALACHIANS FOR THE DURATION OF THE NEAR TERM PERIOD, MAINTAINING
LIGHT SE FLOW ALOFT OF 10-20 KNOTS ACROSS THE TN VALLEY. IN THE
LOWER-LEVELS, OUR REGION WILL REMAIN ALONG THE SOUTHWESTERN FLANK
OF A HIGH OVER THE NORTHWESTERN ATLANTIC, WHICH WILL ENSURE A
CONTINUATION OF LIGHT/VARIABLE FLOW AT THE SURFACE. WITH LINGERING
LIGHT RAIN FROM SHOWERS/THUNDERSTORMS EARLIER TODAY NOW OVER, WE
EXPECT DRY CONDITIONS TO PREVAIL THROUGH THE EARLY MORNING HOURS
ON THURSDAY. HOWEVER, A LOW PROBABILITY FOR REDEVELOPMENT OF A FEW
SHOWERS AND THUNDERSTORMS WILL EXIST FROM NORTHEASTERN MS ACROSS
NORTHWEST AL AND INTO SOUTHERN MIDDLE TN SHORTLY BEFORE SUNRISE AS
A REMNANT MCV (FROM PREVIOUS CONVECTION) BEGINS TO LIFT
NORTHWESTWARD AROUND THE PERIPHERY OF THE ANTICYCLONE ALOFT.
OVERNIGHT LOWS WILL BE A FEW DEGREES COOLER (COMPARED TO LAST
NIGHT) AND IN THE L-M 70S DUE IN PART TO RAIN- COOLED AIR ACROSS
THE REGION. AREAS OF LOCALLY DENSE FOG MAY ALSO DEVELOP
(PARTICULARLY IN LOCATIONS THAT EXPERIENCED WETTING RAINFALL
EARLIER TODAY).
IF SHOWERS AND THUNDERSTORMS BEGIN TO REDEVELOP SHORTLY BEFORE
SUNRISE (AS INDICATED IN SOME MODEL GUIDANCE), THIS ACTIVITY WOULD
LIKELY EXPAND IN COVERAGE THROUGH THE LATE MORNING HOURS AND
SPREAD NORTH-NORTHWESTWARD ACROSS WESTERN TN. HOWEVER, OF MORE
CONCERN FOR OUR CWFA WILL BE DEVELOPMENT OF NEW THUNDERSTORMS
EARLY TOMORROW AFTERNOON AS INTENSE HEATING OCCURS ACROSS THE
CUMBERLAND PLATEAU AND SMOKY MOUNTAINS/SOUTHERN APPALACHIANS. WITH
A LIGHTER AND MORE WESTERLY STEERING FLOW INDICATED IN FORECAST
SOUNDINGS, THIS ACTIVITY WILL BEGIN TO SPREAD INTO EASTERN
PORTIONS OF OUR FORECAST AREA LATE TOMORROW AFTERNOON AND MAY
CONTINUE A BIT LONGER INTO THE EVENING HOURS IF MULTIPLE COLD
POOLS CAN MATERIALIZE. A SIMILAR THERMODYNAMIC PROFILE WILL EXIST
TOMORROW, WITH MLCAPE OF 2500-3500 J/KG, DCAPE OF 1000-1500 J/KG
AND STEEP 0-3KM LAPSE RATES TO SUPPORT A RISK FOR LOCALLY DAMAGING
DOWNBURSTS, SMALL HAIL AND EXCESSIVE LIGHTNING. WITH STRONG
INSOLATION ANTICIPATED FOR MUCH OF THE DAY, HIGHS WILL ONCE AGAIN
REACH THE M-U 90S, WITH DEWPOINTS PERHAPS A FEW DEGREES HIGHER DUE
TO RECENT RAINFALL. THUS, WE WILL CONTINUE THE EXTREME HEAT
WARNING FOR AFTERNOON HI IN THE 108-112F RANGE IN MANY LOCATIONS.
SHORT TERM
(THURSDAY NIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 1121 PM CDT WED JUL 1 2026
DURING THE PERIOD FROM THURSDAY NIGHT-FRIDAY NIGHT, A STRONG
SUBTROPICAL HIGH (INITIALLY ACROSS THE CENTRAL APPALACHIANS) WILL
BEGIN TO WEAKEN AND SHIFT EASTWARD INTO VA/NC AS A NORTHERN STREAM
TROUGH DIGS SOUTHEASTWARD ACROSS ONTARIO/QUEBEC. THIS WILL OCCUR
AS THE AXIS OF A LOW-LEVEL RIDGE SHIFTS SOUTHWARD INTO THE GULF,
AND FOR THIS REASON, STEERING CURRENTS WILL BECOME PROGRESSIVELY
WEAKER AS WE MOVE FORWARD THROUGH THE SHORT TERM PERIOD. A SMALL
COMPLEX OF THUNDERSTORMS WILL LIKELY BE IN PROGRESS ACROSS THE
REGION EARLY TOMORROW EVENING, BUT SHOULD DISSIPATE BETWEEN 2-4Z,
LEAVING ANOTHER WARM/MUGGY NIGHT FEATURING LOWS IN THE L-M 70S
FRIDAY MORNING AND PATCHY FOG IN LOCATIONS THAT EXPERIENCE LATE
AFTERNOON/EVENING RAINFALL. REDEVELOPMENT OF THUNDERSTORMS IS
ANTICIPATED ONCE AGAIN EARLY FRIDAY AFTERNOON ACROSS THE HIGHER
TERRAIN TO OUR NORTH/EAST, WITH SOME OF THIS ACTIVITY LIKELY TO BE
PROPELLED WESTWARD INTO OUR CWFA LATER IN THE AFTERNOON. HOWEVER,
DUE TO WEAKER DEEP-LAYER FLOW, COVERAGE MAY BE CONFINED TO A
SMALLER PORTION OF NORTHEAST AL/SOUTHERN MIDDLE TN BEFORE
DISSIPATION OCCURS FRIDAY EVENING. WITH A SIMILAR THERMODYNAMIC
ENVIRONMENT (COMPARED TO PREVIOUS DAYS) THIS ACTIVITY SHOULD ONCE
AGAIN CARRY A RISK FOR LOCALLY DAMAGING DOWNBURST WINDS, SMALL
HAIL AND EXCESSIVE LIGHTNING.
BY SATURDAY AND SATURDAY NIGHT, THE SUBTROPICAL RIDGE WILL
CONTINUE TO WEAKEN OFF THE COAST OF NC, AND WITH LESS IMPACTS FROM
SUBSIDENCE ALOFT, THE LOCAL ENVIRONMENT WILL BECOME MORE
CONDUCIVE FOR A GREATER SPATIAL COVERAGE OF SHOWERS AND
THUNDERSTORMS. THIS ACTIVITY MAY ALSO BEGIN EARLIER IN THE DAY ON
SATURDAY (PERHAPS AIDED BY ASCENT FROM A MORE DEFINED EASTERLY
WAVE THAT WILL APPROACH THE SOUTHEASTERN ATLANTIC COAST TOMORROW
AND LIFT NORTHWESTWARD INTO AL/MS THIS WEEKEND) AND COULD ALSO
EXTEND FURTHER INTO SATURDAY NIGHT AS OUTFLOW-DRIVEN CONVECTION
FROM STORMS ACROSS MO/IL/IN MAY SPREAD SOUTHEASTWARD INTO THE TN
VALLEY DURING THE EVENING. FORTUNATELY, MID-LEVEL LAPSE RATES WILL
WEAKEN WITH TIME AS LIGHT SOUTHWESTERLY FLOW BECOMES ESTABLISHED
TO THE WEST OF THE 500-MB RIDGE AND TO THE EAST OF A WEAK
SHORTWAVE TROUGH ACROSS THE SOUTHERN PLAINS, AND THIS WILL LESSEN
THE RISK FOR STRONG-SEVERE DOWNBURSTS. HOWEVER, GUSTY WINDS,
LOCALLY HEAVY RAINFALL AND LIGHTNING WILL STILL BE A CONCERN. WITH
AFTERNOON HIGHS GRADUALLY FALLING BACK INTO THE L-M 90S BY
SATURDAY, WE WILL NOT MAKE ANY CHANGES TO THE EXPIRATION TIME OF
THE HEAT ADVISORY.
LONG TERM
(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 1121 PM CDT WED JUL 1 2026
GLOBAL MODELS ARE IN GENERAL AGREEMENT THAT A SUBTROPICAL HIGH IN
THE MID-LEVELS (LOCATED OFF THE SOUTHEASTERN ATLANTIC COAST) WILL
BEGIN TO SLOWLY STRENGTHEN ONCE AGAIN EARLY NEXT WEEK BEFORE
EVENTUALLY RETROGRADING WESTWARD INTO THE NORTHEASTERN GULF. THIS
CONFIGURATION WILL MAINTAIN LIGHT TO MODERATE DEEP-LAYER SW TO WSW
FLOW, PROVIDING ABUNDANT MOISTURE FOR DEVELOPMENT OF SHOWERS AND
THUNDERSTORMS AS A SERIES OF SMALLER SCALE WAVES TRAVEL ALONG THE
EDGE OF THE RIDGE. ALTHOUGH A GRADUAL INCREASE IN SUBSIDENCE ALOFT
MAY KEEP OVERALL COVERAGE OF SHOWERS AND THUNDERSTORMS A BIT
LOWER AT OUR LATITUDE, WE WILL ADVERTISE A 40-60% POP (MAINLY
FOCUSED DURING THE AFTERNOON/EARLY EVENING) EACH DAY FROM SUNDAY-
WEDNESDAY. THE ANTICIPATED COMBINATION OF SHEAR AND INSTABILITY
SUGGESTS THAT CONVECTION WILL BE UNORGANIZED AND SUB-SEVERE, WITH
LIGHTNING AND HEAVY DOWNPOURS THE PRIMARY IMPACTS. DUE TO CLOUDS
AND PRECIPITATION, AFTERNOON HIGHS WILL FALL BACK INTO THE
U80S-L90S BY WEDNESDAY, WITH HEAT RISK DIMINISHING AS WE MOVE
TOWARD THE MIDDLE OF NEXT WEEK.
AVIATION
(00Z TAFS)
ISSUED AT 607 PM CDT WED JUL 1 2026
THUNDERSTORM ACTIVITY HAS BEGUN TO DIE DOWN THIS EVENING OVER THE
TN VALLEY THOUGH A LOW CHANCE WILL LINGER THROUGH SUNSET. THE
MAIN CONCERN OVERNIGHT WILL BE THE POTENTIAL FOR FOG DEVELOPMENT
GIVEN THE RECENT RAINFALL AND EXPECTED CLEAR SKIES. WINDS WILL
REMAIN LIGHT AND VARIABLE OVERNIGHT, ALSO INCREASING THE
CONFIDENCE FOR FOG. ADDITIONAL LOW CHANCES FOR THUNDERSTORMS ARE
IN THE FORECAST THURSDAY AFTERNOON BUT WERE NOT INCLUDED IN THE
TAFS AT THIS TIME GIVEN LOW CONFIDENCE.
HUN WATCHES/WARNINGS/ADVISORIES
AL...EXTREME HEAT WARNING UNTIL 7 PM CDT THURSDAY FOR ALZ001>010-016.
HEAT ADVISORY FROM 7 PM THURSDAY TO 7 PM CDT FRIDAY FOR
ALZ001>010-016.
TN...EXTREME HEAT WARNING UNTIL 7 PM CDT THURSDAY FOR TNZ076-096-097.
HEAT ADVISORY FROM 7 PM THURSDAY TO 7 PM CDT FRIDAY FOR TNZ076-
096-097.
NEAR TERM...70/DD
SHORT TERM...70/DD
LONG TERM...70/DD
AVIATION...25
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page