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Storm Prediction Center Forecast


RSS Mesoscale Discussions from Storm Prediction Center

SPC - No watches are valid as of Wed Jan 22 06:52:01 UTC 2020

No watches are valid as of Wed Jan 22 06:52:01 UTC 2020.


SPC - No MDs are in effect as of Wed Jan 22 06:52:01 UTC 2020

No Mesoscale Discussions are in effect as of Wed Jan 22 06:52:01 UTC 2020.


SPC Jan 22, 2020 0600 UTC Day 1 Convective Outlook

SPC 1200Z Day 1 Outlook
      
Day 1 Outlook Image
Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1134 PM CST Tue Jan 21 2020

Valid 221200Z - 231200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not forecast across the contiguous United
States during the day1 period.

...South TX...

Split flow regime will continue across the CONUS through the day1
period with some amplification expected over the middle of the
country by 23/12z. As heights fall across the southern Plains ahead
of a short-wave trough, a surface wave should form off the south TX
Coast.  This will allow higher boundary-layer air mass to advance
inland across the TX Coastal Plain. In response, a warm front will
sharpen and modified Gulf air mass will move north allowing lower
60s surface dew points to spread onshore along the lower/middle TX
Coast, perhaps approaching the Galveston region by the end of the
period. While this moisture surge is expected to aid buoyancy across
portions of south TX into the lower Sabine River Valley, forecast
shear/instability do not look particularly significant, and not
likely sufficient for organized robust convection. While
near-surface based convection is possible along/south of the warm
front, gusty winds would be the greatest risk with these storms.

..Darrow/Wendt.. 01/22/2020

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SPC Jan 22, 2020 0700 UTC Day 2 Convective Outlook

SPC 0700Z Day 2 Outlook
      
Day 2 Outlook Image
Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1250 AM CST Wed Jan 22 2020

Valid 231200Z - 241200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Thunderstorms are expected Thursday over portions of the central
Gulf Coast states, and possibly into the southern Appalachians late.

...Discussion...
An upper trough -- and evolving closed low -- over the central U.S.
will be the primary feature of interest this period with respect to
the convective forecast, as it shifts gradually eastward and reaches
the middle and lower Mississippi Valley region through latter stages
of the period.  Elsewhere, flanking ridges will prevail, though an
eastern Pacific short-wave trough should reach the Pacific Northwest
overnight.

At the surface, a weak closed low, along the northern extent of an
inverted trough extending northward from the Gulf of Mexico, should
evolve during the second half of the period over the Missouri
vicinity, and then reach the Mid Mississippi Valley by 24/12z.  The
trough/weak front will cross the Lower Mississippi Valley through
the day, and then the central Gulf Coast states and Tennessee Valley
region overnight.

At this time, it remains likely that surface-based instability will
remain confined largely to the northern Gulf of Mexico, with only
minor potential for any higher theta-e air to creep inland.  While a
non-zero severe risk appears to exist over the immediate coastal
areas, primarily across Louisiana's most southern extent, no risk
area will be introduced at this time as potential still appears
unlikely to reach even MRGL risk levels through the period.

...MAXIMUM RISK BY HAZARD...
Tornado:  <2%     - None
Wind:     <5%     - None
Hail:     <5%     - None

..Goss.. 01/22/2020

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SPC Day 1 Fire Weather Outlook

SPC Day 1 Fire Weather Outlook
          
Day 1 Fire Weather Outlook Image
Day 1 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
1232 AM CST Wed Jan 22 2020

Valid 221200Z - 231200Z

...NO CRITICAL AREAS...

...Synopsis...
A mid-level trough will continue to move eastward away from the
eastern Florida coast today. Shortwave ridging will be present
across the southeast in advance of the next trough moving in from
the southern Plains. At the surface, high pressure will remain
across much of the eastern third of the CONUS with a surface cyclone
departing the Bahamas vicinity to the east. While fire weather
concerns across the US will remain low overall, locally elevated
conditions may occur in southern Georgia and the Florida Peninsula.
Portions of Georgia could see RH fall to near 30%, but the strength
of winds may not reach 15 mph. In Florida, winds will be slightly
stronger, but surface flow will become more easterly with time
leading to RH recovering during the day. Whatever locally elevated
conditions do develop will be brief in duration.

..Wendt.. 01/22/2020

...Please see www.spc.noaa.gov/fire for graphic product...

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