WW 642 TORNADO AL MS 182305Z - 190300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 642
NWS Storm Prediction Center Norman OK
505 PM CST Thu Dec 18 2025
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Western and Northern Alabama
Eastern Mississippi
* Effective this Thursday afternoon and evening from 505 PM until
900 PM CST.
* Primary threats include...
A couple tornadoes possible
Scattered damaging wind gusts to 65 mph possible
SUMMARY...A few supercells are forecast to continue to mature and
move east-northeast within a moist and strongly sheared environment
across the Watch area. Gradual destabilization will occur
immediately ahead of the storm activity this evening. The primary
threats accompanying the stronger storms will be damaging gusts and
the possibility for a couple of tornadoes.
The tornado watch area is approximately along and 60 statute miles
east and west of a line from 25 miles north northwest of Huntsville
AL to 70 miles south southwest of Columbus MS. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU2).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.
&&
AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 1 inch. Extreme turbulence and surface wind
gusts to 55 knots. A few cumulonimbi with maximum tops to 350. Mean
storm motion vector 25035.
...Smith
WW 0642 Status Updates
STATUS REPORT ON WW 642
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 NW MEI TO
40 NNE CBM TO 25 NE MSL.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 2264.
..GRAMS..12/19/25
ATTN...WFO...HUN...BMX...JAN...MEG...
STATUS REPORT FOR WT 642
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ALC033-043-057-059-063-075-077-079-083-089-093-103-107-119-125-
127-133-190240-
AL
. ALABAMA COUNTIES INCLUDED ARE
COLBERT CULLMAN FAYETTE
FRANKLIN GREENE LAMAR
LAUDERDALE LAWRENCE LIMESTONE
MADISON MARION MORGAN
PICKENS SUMTER TUSCALOOSA
WALKER WINSTON
MSC069-103-190240-
MS
. MISSISSIPPI COUNTIES INCLUDED ARE
KEMPER NOXUBEE
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
MD 2264 CONCERNING TORNADO WATCH 642... FOR PARTS OF THE DEEP SOUTH
Mesoscale Discussion 2264
NWS Storm Prediction Center Norman OK
0654 PM CST Thu Dec 18 2025
Areas affected...parts of the Deep South
Concerning...Tornado Watch 642...
Valid 190054Z - 190230Z
The severe weather threat for Tornado Watch 642 continues.
SUMMARY...Limited tornado and strong gust threats should persist for
at least a few more hours as broken bands of thunderstorms
consolidate into a line, with the greatest potential across
east-central Mississippi into western Alabama. An additional WW
issuance is unlikely.
DISCUSSION...Earlier supercells have largely diminished, but one is
still ongoing in Newton County, MS. The east-central MS/western AL
area will have the primary near-term tornado threat, owing to its
proximity to modest but weakening buoyancy sampled by the 00Z JAN
sounding. 5.5 to 6 C/km mid-level lapse rates in the JAN/BNA/BMX
soundings will remain a limiting factor to more intense updrafts.
But enlarged low-level hodographs and persistent low 60s surface dew
points will support potential for a tornado or two. Farther
north-northeast, faster propagation of cold front convection
relative to the pre-frontal swath should yield consolidation into a
QLCS that progresses towards the southern Appalachians. Strong gusts
capable of locally damaging winds should be the main threat as
surface-based instability becomes negligible, east and north of
central AL where mid to upper 50s surface dew points persist.
..Grams/Smith.. 12/19/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MRX...OHX...BMX...HUN...MOB...JAN...
LAT...LON 32538919 32868837 33718783 34618766 35068736 35468708
35688639 35648624 35608585 35238575 34808582 34388589
33958607 33538627 32948704 32568752 32408794 32258830
32538919
MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0656 PM CST Thu Dec 18 2025
Valid 190100Z - 191200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE LOWER MISSISSIPPI VALLEY TO THE OHIO VALLEY...
...SUMMARY...
Isolated strong to severe thunderstorms capable of producing
occasional damaging winds, and perhaps a tornado or two, remain
possible this evening across parts of the lower/mid Mississippi
Valley into the Tennessee and Ohio Valleys and Southeast, and late
tonight across portions of coastal North Carolina.
...01z Update...
Strong midlevel trough is advancing across the MS Valley early this
evening. Associated pronounced surface front has surged into
southeast MI-western KY-northwest MS. This boundary will shift
across much of the OH/TN Valleys by late evening as the dynamic
trough induces strong height falls across this region. Latest radar
data reflects this with a strongly forced line of frontal
convection. A few strong gusts have been reported along the northern
sections of this linear MCS. Of potentially more concern is
convection that has developed ahead of the front across eastern MS
into northwest AL. This activity has evolved within a greater
buoyancy air mass characterized by SBCAPE on the order of 500-1000
J/kg. Lower 60s surface dew points have contributed to this
instability and a few supercells have matured and are advancing east
across Tornado Watch #0642. Greatest risk for organized severe will
remain focused across the northern Gulf states this evening.
Damaging winds, along with some tornado risk continues.
Risk of severe will increase late tonight near the Outer Banks
region of NC, and for this region will maintain MRGL Risk.
..Darrow.. 12/19/2025
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0350 PM CST Thu Dec 18 2025
Valid 201200Z - 261200Z
Zonal flow aloft will prevail over the CONUS this weekend, with
ridging slowly building over the southern US next week. Strong flow
aloft will be prevalent around the weak ridging with upper-level
troughing likely off/near the West and Northeast Coasts. This
stronger west-southwest flow aloft will result in downslope flow on
portions of the southern/central High Plains into mid-next week.
Little to no precipitation is expected for much of the Plains for
the forecast period.
...Day 3/Saturday: southern High Plains/vicinity...
West-northwest winds will strengthen ahead of an approaching cold
front and amid dry downslope flow, likely resulting in
elevated/critical fire weather conditions across much of west Texas
into eastern New Mexico. Elevated to locally critical conditions may
extend into the western Hill country and north Texas as boundary
layer mixing routinely extends farther east than longer-range
forecast guidance indicates. The cold front is forecast to arrive in
the evening with breezy/gusty north-northeast winds and no
precipitation, but temperatures will cool and RH will increase with
the frontal passage.
...Day 5/Monday - Day 8/Thursday: southern/central Plains...
Warm/dry conditions will continue on the southern/central Plains
early into late-next week. Downslope flow will mostly continue on
the southern/central High Plains with occasional increases as jets
pass through the background flow. A 40% area was added on Day
5/Monday across northeast New Mexico, southeast Colorado, and the
Oklahoma/Texas Panhandles to reflect this potential. While the
downslope early next week is unlikely to be as strong as this
week's, it will be sufficient for at least locally elevated
conditions on portions of the southern/central High Plains over
multiple days. Additionally, the continued curing of fuels coupled
with the potential of elevated/critical winds/RH in a multi-day
event will be monitored going forward with additional probabilities
likely needed in subsequent outlooks.
..Nauslar.. 12/18/2025
...Please see www.spc.noaa.gov/fire for graphic product...
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