NO TORNADO RISK FORECAST ONLY CHANCE FOR THUNDERSTORMS
SPC AC 231619
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1019 AM CST Wed Nov 23 2022
Valid 231630Z - 241200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
The risk for severe thunderstorms appears negligible across the U.S.
today through tonight.
...Synopsis...
Within a belt of westerlies emanating from the mid-latitude Pacific,
models indicate that there will be further amplification within the
flow across western North America through this period. This likely
will include building mid-level ridging across and inland of the
U.S./British Columbia Pacific coast, and digging mid-level troughing
within split downstream branches near and east of the Rockies. It
still appears that the more amplified of these perturbations will
evolve in the southern branch, and include a developing mid-level
low near the Colorado into New Mexico Rockies later today through
tonight.
Farther downstream, as a deep mid-level low continues to form while
redeveloping across and southeast of the Canadian Maritimes, it
appears that the persistent confluent mid-level regime across the
eastern U.S. may become more focused across and just east of the
Atlantic Seaboard. Beneath this regime, models indicate that cold
surface ridging will be maintained and reinforced across the
Atlantic Seaboard. As some erosion of this ridging commences across
the northwestern Gulf of Mexico into portions of the southern Great
Plains and lower Mississippi Valley, it appears that more prominent
surface ridging, developing across the Intermountain West and
Rockies, will begin to build into the Great Plains. And, surface
cyclogenesis will remain suppressed within weak surface troughing to
the lee of the southern Rockies.
...Southern Great Plains vicinity...
On the southwestern periphery of the eastern surface ridging, modest
low-level moisture return is already underway across and
north-northeast of the lower Rio Grande Valley. A gradual
moistening likely will continue within a narrow plume on the eastern
periphery of a low-level jet (roughly 30+ kt around 850 mb),
north-northeastward toward the Ozark Plateau through daybreak
Thursday. However, this is occurring above an initially cold/stable
surface-based layer. While there probably will be some modification
of this air mass today through tonight, low cloud cover and
precipitation will contribute to the maintenance of a substantive
low-level/near-surface inversion layer across most areas north of
the middle Texas coastal plain. Weak boundary-layer destabilization
appears possible overnight across the coastal plain, but this seems
likely to remain capped beneath warming layers aloft.
North of a College Station/Temple line into areas near/northwest of
the Ark-La-Tex, strengthening large-scale forcing for ascent is
expected to support increasing thunderstorm development late this
evening into the overnight hours. Modest to weak elevated
instability and shear (within the relevant potential convective
layer) likely will minimize the risk for severe weather.
..Kerr/Thornton.. 11/23/2022
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z
CURRENT UTC TIME: 1707Z (12:07PM), RELOAD THIS PAGE TO UPDATE THE TIMEDAY 2 SEVERE STORM OUTLOOK
THERE IS A CHANCE FOR TORNADO SEE NEXT PROBABILITY GRAHPHICS
SPC AC 230508 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1108 PM CST Tue Nov 22 2022 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PORTIONS OF SOUTHEAST TEXAS INTO SOUTHWEST LOUISIANA... ...SUMMARY... Isolated strong to severe thunderstorms are possible Thursday afternoon and evening across the Middle and Upper Texas Coast vicinity into southwest Louisiana. Locally damaging gusts and perhaps a tornado will be possible. ...Middle and Upper TX Coast/Southeast TX/Southwest LA... A positive-tilt large-scale upper trough will extend from the northern Plains to the southern Rockies early Thursday. Forecast guidance continues to vary with the eastward evolution of the southern branch of the trough over the southern Plains. Guidance has generally trended toward a cut-off upper low developing over the southern High Plains, and only shifting slightly eastward by Friday morning, though the deterministic GFS in particular is now maintaining an open wave and somewhat more progressive trough compared to earlier runs. Nevertheless, ensemble guidance still is indicating preference toward a cut-off upper low developing, bringing enhanced southwesterly mid/upper level flow over southern/eastern TX and the lower MS Valley vicinity. At the surface, a trough will extend from western OK into central TX, while a cold front shifts southeast across TX/OK/AR through the period. Uncertainty still remains regarding surface cyclogenesis across TX into the central Gulf coast. The expectation is that only modest surface cyclogenesis will occur, limiting rich boundary-layer moisture (mid/upper 60s F dewpoints) to the Middle/Upper TX Coasts/southeast TX and coastal Louisiana. While the surface cold front shifts southeast through the period, a warm front is expected to remain just offshore from the LA coast. Numerous showers and scattered thunderstorms will be ongoing Thursday morning, limiting destabilization despite mid/upper 60s F dewpoints. A few strong to severe thunderstorms may develop during the afternoon/evening ahead of the cold front as forcing for ascent increases. Low-level winds will remain modest, generally less than 25 kt through around 3km. However, vertically veering wind profiles, with moderate to strong mid/upper level flow will support 40+ kt effective shear magnitudes. This will aid in updraft organization, though longevity/intensity of organized cells may be tempered by poor thermodynamics. As a result, will maintain a Marginal (level 1 of 5) risk primarily for a few damaging gusts and perhaps a tornado. ..Leitman.. 11/23/2022 CLICK TO GET WUUS02 PTSDY2 PRODUCT NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z CURRENT UTC TIME: 1715Z (12:15PM), RELOAD THIS PAGE TO UPDATE THE TIME
DAY 2 TORNADO PROBABILITY
DAY 2 DAMAGING WIND OUTLOOKTHERE IS NO CHANCE FOR DAMAGING HAIL EXPECTED!WPC DAY 1-3 NATIONAL FORECAST CHARTS ANIMATIONDAY 1-3 SNOWFALL PROBABILITY GREATER THAN 4 INCHES
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