438
FXUS64 KHUN 190530
AFDHUN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HUNTSVILLE AL
1230 AM CDT FRI JUN 19 2026
..NEW AVIATION
KEY MESSAGES
UPDATED AT 1053 PM CDT THU JUN 18 2026
- THERE IS A LOW (10-30%) CHANCE FOR ADDITIONAL SHOWERS AND
THUNDERSTORMS OVERNIGHT AS A WEAK COLD FRONT ENTERS THE REGION.
THE COVERAGE OF SHOWERS AND STORMS WILL BE MOST CONCENTRATED
SOUTH OF THE TN RIVER TOMORROW.
- AFTER A BRIEF PERIOD OF DRY WEATHER LATE FRIDAY INTO SATURDAY
MORNING, ADDITIONAL ROUNDS OF RAIN AND THUNDERSTORMS ARE
FORECAST INTO THE LONG TERM PERIOD WITH HIGH RAIN CHANCES
SUNDAY-MONDAY NIGHT.
NEAR TERM
(THIS EVENING THROUGH FRIDAY)
ISSUED AT 1053 PM CDT THU JUN 18 2026
THE REMNANTS OF TC ARTHUR WILL CONTINUE TO ACCELERATE EAST-
NORTHEASTWARD ACROSS NORTHERN GA THIS EVENING AND INTO NORTH-
CENTRAL SC BY 12Z FRIDAY, WITH LIGHT STRATIFORM RAIN ALONG THE
NORTHWESTERN PERIPHERY OF ITS CIRCULATION EXPECTED TO END IN OUR
SOUTHEASTERN ZONES BY 3Z. MEANWHILE, A COLD FRONT CURRENTLY
EXTENDS FROM THE UPPER OH VALLEY SOUTHWESTWARD THROUGH CENTRAL
KY/WESTERN TN TO A SMALL LOW OVER CENTRAL AR, BEFORE TRANSITIONING
TO A STATIONARY FRONT THAT EXTENDS WEST-SOUTHWESTWARD TO A LEE
CYCLONE ACROSS THE SOUTHERN TX PANHANDLE. ALTHOUGH SHOWERS AND
THUNDERSTORMS OCCURRING IN THE VICINITY OF THE FRONT HAVE LARGELY
DISSIPATED WITH THE ONSET OF THE NOCTURNAL COOLING CYCLE, THERE IS
SOME CONCERN THAT A FEW CONVECTIVE CELLS MAY DEVELOP AS THE
LEADING EDGE OF THE SLIGHTLY DRIER CONTINENTAL AIRMASS SHIFTS
SOUTHWARD AND APPROACHES THE AL-TN BORDER BETWEEN 9-12Z. AT THIS
POINT, THE RISK FOR THUNDERSTORMS APPEARS LOW (BUT NON-ZERO WITH
CAPE IN THE 500-750 J/KG RANGE) AND ANTICIPATED COVERAGE ONLY
APPEARS TO WARRANT A 20-30% POP AS THE GREATEST CONCENTRATION OF
NOCTURNAL CONVECTION SHOULD OCCUR ACROSS A CORRIDOR FROM SOUTH-
CENTRAL KS INTO NORTHERN AR (SLIGHTLY NORTH OF THE SURFACE FRONT)
WHERE ELEVATED WARM ADVECTION (RELATED TO AN AMPLIFYING SHORTWAVE
OVER IA/MO) WILL BE MAXIMIZED. OTHERWISE, OVERNIGHT LOWS WILL BE A
FEW DEGREES COOLER TONIGHT (U60S-L70S) DUE PRIMARILY TO COOLER
AFTERNOON TEMPS EARLIER TODAY, WITH DEVELOPMENT OF PATCHY FOG/LOW
STRATUS CLOUDS PRIOR TO SUNRISE.
DURING THE DAY TOMORROW, THE CENTER OF A MODIFIED CANADIAN
ANTICYCLONE WILL BUILD SOUTHEASTWARD FROM THE CENTRAL PLAINS INTO
THE LOWER OH VALLEY, FORCING THE LEADING EDGE OF THE DRIER
CONTINENTAL AIRMASS FURTHER SOUTHWARD THROUGH OUR CWFA. PRESENT
INDICATIONS ARE THAT THUNDERSTORMS WILL REDEVELOP IN THE VICINITY
OF THE MOISTURE GRADIENT OVER THE COURSE OF THE MORNING, WITH
ADDITIONAL CLUSTERS OF STORMS PERHAPS SPREADING SOUTHEASTWARD FROM
AR BENEATH NW FLOW ALOFT OF 25-35 KNOTS. ALTHOUGH IT IS UNCLEAR
AT THIS POINT PRECISELY HOW FAR SOUTHWARD THE BOUNDARY WILL REACH
BEFORE CONVECTIVE INITIATION BEGINS, IT SEEMS REASONABLE TO
ADVERTISE A GRADIENT IN POPS RANGING FROM 10-20% (NORTH) TO 30-40%
(SOUTH). HOWEVER, THE GREATEST COVERAGE OF STORMS TOMORROW SHOULD
EXIST ACROSS CENTRAL/SOUTHERN PORTIONS OF AL. WITH ONLY A LIGHT
NNW WIND AND MOSTLY SUNNY SKIES NORTH OF THE FRONT, AFTERNOON
HIGHS WILL BE SIMILAR COMPARED TO TODAY (L-M 80S).
SHORT TERM
(FRIDAY NIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 1053 PM CDT THU JUN 18 2026
SURFACE HIGH PRESSURE WILL CONTINUE TO SPREAD SOUTHEASTWARD INTO
THE SOUTHERN APPALACHIANS ON FRIDAY NIGHT, WITH A LIGHT NORTHEAST
WIND ALLOWING BOTH AIR TEMPS AND DEWPOINTS TO FALL INTO THE L-M
60S. THUS, WE EXPECT DRY CONDITIONS (AFTER ANY AFTERNOON SHOWERS
AND STORMS DISSIPATE SOUTH OF THE TN RIVER), WITH PATCHY FOG IN A
FEW OF OUR NORMALLY FOG-PRONE LOCATIONS. DURING THE DAY ON
SATURDAY, THE STALLED BOUNDARY TO OUR SOUTH WILL BEGIN TO LIFT
NORTHWARD AS A WARM FRONT IN RESPONSE TO THE EAST-NORTHEASTWARD
MOVEMENT OF A MID-LEVEL SHORTWAVE TROUGH ACROSS THE GREAT BASIN
AND SUBSEQUENT DEVELOPMENT OF A RATHER IMPRESSIVE SURFACE LOW
ACROSS EASTERN CO. SCATTERED SHOWERS AND THUNDERSTORMS MAY DEVELOP
OVER THE COURSE OF THE AFTERNOON AS THE MOIST AIRMASS BEGINS TO
RETURN NORTHWARD, BUT AT THIS POINT IT APPEARS AS IF CONVECTION
WILL BE MOST CONCENTRATED ACROSS THE SOUTHWESTERN PORTION OF THE
FORECAST AREA (WHERE POPS ARE IN THE 20-30% RANGE). AS THE LEE LOW
BEGINS TO MIGRATE EAST-NORTHEASTWARD ACROSS KS ON SATURDAY NIGHT,
LOW-LEVEL SSE FLOW WILL GRADUALLY STRENGTHEN WITH DEWPOINTS
RISING INTO THE LOWER 70S REGION-WIDE BY SUNDAY MORNING. ALTHOUGH
A FEW SHOWERS MAY OCCUR AT TIMES, POPS REMAIN RATHER LOW AND IN
THE 10-20% RANGE.
ON SUNDAY AND SUNDAY NIGHT, MODELS SUGGEST THAT THE DOMINANT
SYNOPTIC SURFACE LOW WILL ADVANCE FURTHER EAST-NORTHEASTWARD
ACROSS THE MID-MS VALLEY AND INTO NORTHERN OH (IN CONJUNCTION WITH
THE MID-LEVEL SHORTWAVE TROUGH). THIS CONFIGURATION WILL INDUCE
STRENGTHENING SOUTHWESTERLY FLOW THROUGHOUT THE DEPTH OF THE
TROPOSPHERIC COLUMN ACROSS OUR REGION, WITH PWAT VALUES SURGING
BACK INTO THE 1.8-2" RANGE. A FAIRLY WIDESPREAD COVERAGE OF
THUNDERSTORMS IS EXPECTED TO EVOLVE OVER THE COURSE OF THE DAY
FROM SOUTHERN MS NORTHEASTWARD INTO TN/KY (PERHAPS AIDED BY AN MCV
FROM A NOCTURNAL MCS OVER THE MO VALLEY), BUT ALTHOUGH RICH
TROPICAL MOISTURE MAY LEAD TO VERY HIGH RAINFALL RATES, CELLS WILL
BE MOVING RATHER QUICKLY TO THE NORTHEAST IN THIS REGIME, WHICH
SHOULD LIMIT CONCERN FOR FLOODING. HOWEVER, DUE TO HIGHER CAPE AND
STRONGER LOW/MID-LEVEL FLOW, STORMS MAY BE CAPABLE OF PRODUCING
MORE FREQUENT WIND GUSTS IN THE 40-50 MPH RANGE. ALTHOUGH
AFTERNOON CONVECTION ACROSS THE OPEN WARM SECTOR WILL EXHIBIT A
WEAKENING TREND AND SHOULD DISSIPATE SHORTLY AFTER SUNSET, THERE
ARE INDICATIONS THAT A LARGE MCS (PERHAPS INCLUDING MULTIPLE
BOWING SEGMENTS) MAY EVOLVE IN THE VICINITY OF THE TRAILING COLD
FRONT SUNDAY EVENING FROM EASTERN KS INTO WESTERN IL. THE LEADING
EDGE OF THIS SYSTEM MAY APPROACH OUR FORECAST AREA PRIOR TO
SUNRISE ON MONDAY, AT WHICH POINT THE WSW LOW-LEVEL JET SHOULD BE
PEAKING IN THE 35-40 KNOT RANGE. FORTUNATELY, FORECAST SOUNDINGS
SUGGEST THAT CONVECTION MAY BE SLIGHTLY ELEVATED ABOVE A STRONG
LOW-LEVEL INVERSION, BUT IF THIS DOES NOT MATERIALIZE, THIS
ACTIVITY WOULD CARRY A RISK FOR BOTH SEVERE WIND GUSTS AND PERHAPS
A FEW TORNADOES AS WELL.
LONG TERM
(MONDAY THROUGH THURSDAY)
ISSUED AT 1053 PM CDT THU JUN 18 2026
A HIGH COVERAGE OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO
CONTINUE THROUGHOUT THE DAY ON MONDAY AND INTO MONDAY NIGHT AS A
SURFACE LOW EJECTS NORTHEASTWARD OFF THE COAST OF NEW ENGLAND AND
A TRAILING COLD FRONT SLIPS SLOWLY SOUTHEASTWARD. ALTHOUGH
MULTIPLE ROUNDS OF CONVECTION MAY ULTIMATELY HAVE AN IMPACT ON
INSTABILITY, FORECAST SOUNDINGS INDICATE A FAVORABLE COMBINATION
OF HIGH CAPE AND SUFFICIENTLY STRONG LOW/MID-LEVEL FLOW THAT WOULD
BE CONDUCIVE FOR ORGANIZED/SEVERE THUNDERSTORMS DURING THIS
TIMEFRAME. AS FOR THE REMAINDER OF THE PERIOD, THERE ARE SUBTLE
DIFFERENCES WITHIN THE SUITE OF GUIDANCE REGARDING HOW FAR SOUTH
THE COLD FRONT (AND A REINFORCING SURGE OF DRIER CONTINENTAL AIR
IN ITS WAKE) WILL PUSH BEFORE EVENTUALLY STALLING. DUE TO THIS
UNCERTAINTY, WE WILL MAINTAIN POPS IN THE 20-40% RANGE (HIGHEST
DURING THE AFTERNOON). FORTUNATELY, IT APPEARS AS IF THE STORM
ENVIRONMENT FOR THE REST OF THE WEEK WILL FEATURE LIGHTER LOW/MID-
LEVEL FLOW AND SHEAR (REDUCING THE RISK FOR ORGANIZED
CONVECTION). HOWEVER, LAPSE RATES ALOFT WILL REMAIN STEEP IN THE
WEST- NORTHWEST FLOW REGIME, AND HIGH CAPE MAY STILL YIELD A RISK
FOR LOCALLY DAMAGING DOWNBURST WINDS ON A DAILY BASIS.
TEMPERATURES WILL FLUCTUATE VERY LITTLE THROUGHOUT THE EXTENDED
PERIOD, WITH HIGHS IN THE L-M 80S AND LOWS IN THE M-U 60S.
AVIATION
(06Z TAFS)
ISSUED AT 1230 AM CDT THU JUN 19 2026
SOME MVFR CIGS AROUND 3000 FEET CAN BE SEEN IN OBSERVATIONS NEAR
BOTH TERMINALS. HOWEVER, BOTH KMSL AND KHSV ARE EITHER STILL
PARTLY CLOUDY OR CURRENTLY HAVE HIGH CIGS OVER THE TERMINAL. GIVEN
LIGHT WINDS, SOME PATCHY FOG PRODUCING MVFR VSBY CONDITIONS WAS
INCLUDED AT BOTH TERMINALS IN A TEMPO GROUP AT TIMES BETWEEN 6Z
AND 8Z ALONG WITH MVFR CIGS. EXPECT THESE CONDITIONS TO BECOME
PREDOMINANT AHEAD OF AN APPROACHING COLD FRONT TO THE NORTH OF THE
TERMINALS AROUND 8Z. A LOW CHANCE OF SHOWERS (10 TO 30 PERCENT)
WAS ACCOUNTED FOR AT BOTH TERMINALS WITH A PROB30 GROUP BETWEEN 9Z
AND 13Z NEAR AND BEHIND THAT FRONT BEFORE IT PUSHES FAR ENOUGH SE
OF THE TERMINALS. CIGS COULD DROP TO BELOW 1000 FEET WITH ANY
SHOWERS AT TIMES, BUT CIGS SHOULD REMAIN PREDOMINANTLY MVFR. VFR
CONDITIONS AND NW WINDS BETWEEN 5 AND 10 KNOTS ARE EXPECTED BY 14Z
AT KMSL AND 15Z AT KHSV.
HUN WATCHES/WARNINGS/ADVISORIES
AL...NONE.
TN...NONE.
NEAR TERM...70
SHORT TERM....70
LONG TERM....70
AVIATION...KTW
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