SPC AC 081603
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1003 AM CST Mon Dec 08 2025
Valid 081630Z - 091200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe thunderstorms are not expected through tonight.
...Synopsis and Discussion...
A progressive upper pattern will persist today with a pair of
shortwave troughs, one currently moving towards the central
Appalachians and the other moving towards the Four Corners and
central Rockies, continuing eastward/southeastward as another pair
of shortwave troughs drop into the northern Plains and Upper
Midwest. At the surface, high pressure will continue to shift
eastward/southeastward over more of the eastern CONUS while a low,
currently in the western Atlantic off the SC coast, progresses
northeastward.
A cold front extends southwestward from the western Atlantic surface
low through central FL, which is the only area across the entire
CONUS with any notable low-level moisture. Dewpoints over south FL
preceding this front are currently in the low 70s, and mesoanalysis
indicates modest buoyancy over the region. Convergence along the
front will be modest and much of the large-scale ascent will be
displaced north and east of this region, but isolated showers and
thunderstorms are still expected this afternoon and evening.
Moderate deep-layer vertical shear is in place, and there is a
very-low-probability risk for a damaging gust or two. However,
limited updraft depth and/or persistence should mitigate the overall
severe potential.
..Mosier/Leitman.. 12/08/2025
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z
SPC AC 080501
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1101 PM CST Sun Dec 07 2025
Valid 091200Z - 101200Z
...NO THUNDERSTORM AREAS FORECAST...
...SUMMARY...
The risk for thunderstorms appears negligible across the U.S Tuesday
through Tuesday night.
...Discussion...
While a blocking high to the north of the Aleutians may undergo at
least some short-lived suppression, models indicate that a
downstream high may become a bit more prominent across the southern
mid- to subtropical latitudes of the eastern Pacific during this
period. As this occurs, a belt of strong anticyclonic flow is
likely to be maintained across much of the eastern mid-latitude
Pacific through the northern U.S. intermountain region and Rockies.
One of a number of short wave perturbations progressing through this
jet is forecast to emerge and contribute to amplifying mid-level
troughing as it digs across the northern Great Plains through Upper
Midwest, accompanied by a rapidly migrating surface cyclone into the
upper Great Lakes by late Tuesday night. It appears that this will
be trailed by a gradually consolidating and increasingly significant
surface cold intrusion.
A notable preceding surface front may remain a focus for
thunderstorm development near and south-southeast of the Florida
Straits Tuesday into Tuesday night. The trailing flank of this
front is forecast to weaken across the southwestern Gulf Basin, and
some Gulf boundary-layer modification may commence to the north.
However, this is likely to remain rather modest, and an initial
low-level offshore flow across the Gulf Coast, veering to an
increasing westerly component by Tuesday night, will tend to inhibit
inland moistening.
..Kerr.. 12/08/2025
WUUS02 PTSDY2
SPC AC 080727
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0127 AM CST Mon Dec 08 2025
Valid 101200Z - 111200Z
...NO THUNDERSTORM AREAS FORECAST...
...SUMMARY...
The risk for thunderstorms appears negligible across the U.S.
Wednesday through Wednesday night.
...Discussion...
Models indicate that an increasingly prominent high may build once
again across and north of the Aleutians vicinity, but it appears
that there will be little change to the downstream flow across the
mid-latitude eastern Pacific into western North America, through at
least this period. Downstream, there is substantive spread in the
model output concerning the subsequent evolution of short wave
troughing initially digging across the Midwest at the outset of the
period, and another notable perturbation digging toward the Great
Lakes region, after emerging from the southern Hudson Bay vicinity.
Regardless, larger-scale mid/upper troughing to the east of the
Rockies will be reinforced, and related surface developments are not
likely to promote a southerly return flow off the Gulf Basin, where
boundary-layer modification in the wake of the prior front will only
be gradually underway.
..Kerr.. 12/08/2025
WUUS03 PTSDY3
NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 1930Z
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