SPC - No watches are valid as of Mon Feb 24 20:16:01 UTC 2020

No watches are valid as of Mon Feb 24 20:16:01 UTC 2020.


No Mesoscale Discussions are in effect as of Mon Feb 24 20:16:01 UTC 2020.

SPC Feb 24, 2020 1630 UTC Day 1 Convective Outlook

SPC 1630Z Day 1 Outlook
      
Day 1 Outlook Image
Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1013 AM CST Mon Feb 24 2020

Valid 241630Z - 251200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE MIDDLE AND LOWER MISSISSIPPI VALLEY...

...SUMMARY...
Isolated marginally severe storms are possible from southern
Missouri into northern Mississippi during the afternoon and early
evening.

...Mid/Lower Mississippi Valley...
A strong and progressive shortwave trough and associated 80-90 knot
midlevel jet max is tracking across KS/OK/AR.  A relatively deep
surface low over northeast OK will track eastward across southern
MO/northern AR through the day, with a trailing pacific front
sweeping across AR and eventually into parts of TN/MS.  This
boundary will be the focus for convective development by
mid-afternoon as low-level moisture increases and partial clearing
occurs. 

A consensus of 12z CAMS suggest that low-topped thunderstorms will
develop 21-23z over eastern AR and spread eastward across the MRGL
risk area.  Forecast soundings show that storms will likely be
surface-based, but will struggle to attain significant intensity due
to limited moisture/instability.  Nevertheless, a few of the storms
may become strong for an hour or two with the potential for hail,
gusty winds, or even a brief tornado.

...FL Panhandle...
Increasing low-level moisture will eventually lead to the potential
for surface-based thunderstorms over parts of the FL Panhandle and
southeast AL this evening.  Forecast soundings suggest sufficient
CAPE/shear profiles for a conditional risk of a rotating storm or
two, but weak large-scale forcing and little signal in models for
robust updrafts suggest overall threat is low.

..Hart/Mosier.. 02/24/2020

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SPC Feb 24, 2020 2000 UTC Day 1 Convective Outlook

SPC 2000Z Day 1 Outlook
      
Day 1 Outlook Image
Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0147 PM CST Mon Feb 24 2020

Valid 242000Z - 251200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF
SOUTHERN MISSOURI...NORTHEAST ARKANSAS...FAR WESTERN KENTUCKY AND
WESTERN TENNESSEE...AND FAR NORTHERN MISSISSIPPI...

...SUMMARY...
Isolated marginally severe storms are possible from southern
Missouri into northern Mississippi during the afternoon and early
evening.

...Discussion...
Only minor changes in the Marginal Risk have been made to the
previous convective outlook.  Model data suggests the ongoing
convective band located over AR this afternoon will continue to
develop east-northeastward over the next several hours.  Peak
intensity of the convective line will likely occur this afternoon
with weakening expected by early evening.  Current thinking is the
window of opportunity will become increasingly limited for northern
MS to appreciably destabilize.  Given the proximity to stratiform
rain over central MS, have reduced probabilities over much of
northern MS to account for the stratiform rain's stabilizing
influence of the MS boundary layer.

..Smith.. 02/24/2020

.PREV DISCUSSION... /ISSUED 1013 AM CST Mon Feb 24 2020/

...Mid/Lower Mississippi Valley...
A strong and progressive shortwave trough and associated 80-90 knot
midlevel jet max is tracking across KS/OK/AR.  A relatively deep
surface low over northeast OK will track eastward across southern
MO/northern AR through the day, with a trailing pacific front
sweeping across AR and eventually into parts of TN/MS.  This
boundary will be the focus for convective development by
mid-afternoon as low-level moisture increases and partial clearing
occurs. 

A consensus of 12z CAMS suggest that low-topped thunderstorms will
develop 21-23z over eastern AR and spread eastward across the MRGL
risk area.  Forecast soundings show that storms will likely be
surface-based, but will struggle to attain significant intensity due
to limited moisture/instability.  Nevertheless, a few of the storms
may become strong for an hour or two with the potential for hail,
gusty winds, or even a brief tornado.

...FL Panhandle...
Increasing low-level moisture will eventually lead to the potential
for surface-based thunderstorms over parts of the FL Panhandle and
southeast AL this evening.  Forecast soundings suggest sufficient
CAPE/shear profiles for a conditional risk of a rotating storm or
two, but weak large-scale forcing and little signal in models for
robust updrafts suggest overall threat is low.

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SPC Feb 24, 2020 1730 UTC Day 2 Convective Outlook

SPC 1730Z Day 2 Outlook
      
Day 2 Outlook Image
Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1056 AM CST Mon Feb 24 2020

Valid 251200Z - 261200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not currently forecast in the Lower 48
states on Tuesday.

...Synopsis...
A longwave mid-level trough situated over the Great Plains will
slowly move to the MS Valley during the day 2 period.  As this
occurs, the primary disturbance embedded within the trough will
amplify as it moves from the central Great Plains to the lower MS
Valley.  Downstream over the Southeast, strong southwesterly flow
aloft will be maintained (neutral mid-level heights) from the Gulf
of Mexico northeastward into the Carolinas.  In the low levels, an
occluding surface low over the OH Valley/central Appalachians will
weaken during the day as a frontal zone moves slowly eastward across
parts of the Southeast.  

Low-level moisture is forecast to gradually increase into the mid
60s over the northeast Gulf Coast with lower 60s farther north over
central GA and the Carolina coastal plain.  Relatively weak lapse
rates will limit the magnitude of buoyancy with MLCAPE in the
200-500 J/kg range.  Isolated thunderstorms are forecast primarily
during the morning but thunderstorm development may continue into
peak heating.  Combined with the weak instability, modest low-level
flow and nebulous large-scale forcing for ascent will likely
preclude an organized severe risk.  Although a strong storm or two
cannot be ruled out (perhaps near the northeast Gulf Coast), severe
probabilities do not appear warranted this forecast update.

..Smith.. 02/24/2020

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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
1007 AM CST Mon Feb 24 2020

Valid 241700Z - 251200Z

The previous forecast remains largely on track. In addition, a
relatively dry surface airmass remains in place across the eastern
Mid Atlantic (RH dropping to 35% in some locations), which will lead
to further drying of the finer fuels. Nonetheless, the lack of a
stronger wind field and warmer temperatures preclude an elevated
area delineation.

Please see the previous forecast below for more details.

..Squitieri.. 02/24/2020

.PREV DISCUSSION... /ISSUED 1256 AM CST Mon Feb 24 2020/

...Synopsis...
A vigorous mid-level trough will develop across the central Rockies
in the wake of a lead wave traversing the Mid-Mississippi Valley and
vicinity.  Lee surface cyclogenesis will develop in response to this
troughing across the Texas South Plains and vicinity during the
afternoon.  This will encourage a fire-weather threat to develop in
the southern High Plains, though this threat will be tempered by
uncured fuels in several areas.

...Eastern New Mexico and far west Texas...
Along and west of the surface low/trough, substantial heating and
drying will take place during the afternoon.  RH values will fall as
low as single digits in some areas of east-central New Mexico, while
falling to higher values (around 15-25%) in west Texas.  This,
combined with wind speeds approaching 30 mph in a few areas, will
foster development of critical atmospheric conditions.  The limiting
factor for a higher fire-weather risk is fuel states, with portions
of the region experiencing wetting rainfall over the past 24 hours. 
Thus, an elevated fire-weather delineation is in place to address
the threat.

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

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SPC Day 2 Fire Weather Outlook

SPC Day 2 Fire Weather Outlook
          
Day 2 Fire Weather Outlook Image
Day 2 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
1251 PM CST Mon Feb 24 2020

Valid 251200Z - 261200Z

Much of the forecast remains on track. A few modifications were made
to the Southern California/Lower Colorado River Valley elevated
area, with the delineation trimmed back to the areas where fuels
with the relatively highest receptiveness for wildfire spread exist.

Please see the previous forecast below for more details.

..Squitieri.. 02/24/2020

.PREV DISCUSSION... /ISSUED 1258 AM CST Mon Feb 24 2020/

...Synopsis...
A strong surface high (>1042 mb) will settle into portions of the
central Rockies and eastern Great Basin D2/Tue.  As this occurs, a
favorable pressure gradient will set up for gusty winds to occur in
a broad part of the southwestern U.S. from southern California
eastward to west Texas.  The dry, continental airmass across the
region will warm and lead to elevated fire-weather conditions,
though unfavorable fuels in many areas should keep any critical
fire-weather conditions very localized.

...Southern New Mexico and west Texas...
Central Rockies high pressure and a front/surface low near south
Texas will foster development of widespread areas of 20-35 mph
surface winds with a few higher gusts in terrain-favored areas.
These winds will occur within a dry airmass, with RH values falling
to the single digits across New Mexico despite surface temperatures
only reaching the upper 40s F in some of those areas.  Slightly
higher RH values are expected near the Rio Grande Valley, though
10-20% values will become common during peak heating.  Again, recent
rainfall and low ERCs are expected to limit the extent of the
fire-weather threat in these areas, though if finer fuels can carry
large fires, critical atmospheric fire-weather conditions will
exist.

...Southern California and the Lower Colorado River Valley...
A similar regime for easterly/northeasterly flow will exist across
these areas in response to the very strong area of high pressure
across the central Rockies and surface trough located roughly along
the California coast.  25-35 mph surface winds will become common
across the area, with higher gusts possible across terrain-favored
areas of southern California coastal ranges.  These winds will occur
amidst critically low RH values ranging from 3-15% across the
region.  Where fuels are dry, critical fire weather conditions will
exist - however the extent of critically dry fuels is expected to be
limited.

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

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