SPC - No watches are valid as of Tue Nov 13 21:08:02 UTC 2018

No watches are valid as of Tue Nov 13 21:08:02 UTC 2018.


No Mesoscale Discussions are in effect as of Tue Nov 13 21:08:02 UTC 2018.

SPC Nov 13, 2018 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
1021 AM CST Tue Nov 13 2018

Valid 131630Z - 141200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not expected today.

...FL/GA...
Virtually no changes have been made to the ongoing forecast. 
Scattered showers and isolated thunderstorms will be possible today
and tonight over parts of southern GA and much of FL.  Forecast
soundings show poor lapse rates and minimal convergence/shear,
suggesting that lightning activity will be limited over land, and
the severe threat is low.

..Hart/Bentley.. 11/13/2018

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SPC Nov 13, 2018 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
0125 PM CST Tue Nov 13 2018

Valid 132000Z - 141200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not expected today.

...20Z Outlook Update...
Only minor changes have been made to the categorical (10 percent)
risk of thunderstorms line, mainly to account for the progression of
the cold front.  The front continues to advance slowly
southeastward, beneath the northwestern periphery of  mid-level
subtropical ridging centered over the southwestern Atlantic.

Relatively warm mid-level temperatures may generally tend to
suppress convection developing in response to daytime heating of the
moist boundary layer over the Florida Peninsula.  But a couple of
showers have begun to generate a few lightning strikes, and similar
such isolated to widely scattered activity may continue into  this
evening.

..Kerr.. 11/13/2018

.PREV DISCUSSION... /ISSUED 1021 AM CST Tue Nov 13 2018/

...FL/GA...
Virtually no changes have been made to the ongoing forecast. 
Scattered showers and isolated thunderstorms will be possible today
and tonight over parts of southern GA and much of FL.  Forecast
soundings show poor lapse rates and minimal convergence/shear,
suggesting that lightning activity will be limited over land, and
the severe threat is low.

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SPC Nov 13, 2018 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
1101 AM CST Tue Nov 13 2018

Valid 141200Z - 151200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
The risk for severe thunderstorms appears negligible across the U.S.
Wednesday through Wednesday night.

...Discussion...
The westerlies appear likely to trend less amplified, but cold/dry
and/or stable conditions now present across much of the nation will
be slow to modify through this period.

Models do continue to indicate that fairly significant lower/mid
tropospheric cyclogenesis may occur within a remnant southern branch
of mid-latitude westerlies, from the southern Plains through the Mid
South region by late Wednesday night.  This will occur generally
above/to the northwest of the shallow leading edge of the ongoing
low-level arctic intrusion, which is expected to advance off the
south Atlantic coast, into northern Florida, and through much of the
northern/western Gulf of Mexico by 12Z Wednesday.  However, it
appears that associated forcing will contribute to a developing
surface low across the Tennessee Valley, and a bit more prominent
surface frontal wave from the northeastern Gulf of Mexico into the
vicinity of the South Carolina coast, Wednesday through Wednesday
night.

This may be accompanied by sufficient destabilization to support a
risk for weak thunderstorm activity above the cold/stable surface
based air, mainly along the frontal zone across parts of northern
Florida and the Florida Panhandle into the piedmont and coastal
plain of the Carolinas.  However, the spread among the various model
output appears sizable concerning the extent of this potential, and
the possibility of isolated thunderstorm activity across the Florida
Peninsula.  Highest thunderstorm probabilities probably will remain
focused along the front east of the south Atlantic coast, and
perhaps across parts of the southeastern Gulf of Mexico.  Across and
inland of coastal areas, the risk for severe storms still appears
negligible.

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

..Kerr.. 11/13/2018

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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
1249 PM CST Tue Nov 13 2018

Valid 141200Z - 151200Z

...CRITICAL FIRE WEATHER AREA FOR SAN GABRIEL MOUNTAINS VICINITY...
...CRITICAL FIRE WEATHER AREA FOR SAN JACINTO TO LAGUNA MOUNTAIN
RANGES...

No changes are needed to the previous forecast. The development of
critical fire-weather conditions appears likely, confined mostly to
the San Gabriel and San Jacinto/Laguna Mountains. Areas in between
these two mountain ranges will be quite dry, but current model
guidance still suggests winds will not be as strong as adjacent
areas.  The possibility of connecting the two critical areas will
monitored in subsequent outlooks as higher-resolution model guidance
becomes available.

..Karstens.. 11/13/2018

.PREV DISCUSSION... /ISSUED 0130 AM CST Tue Nov 13 2018/

...Synopsis...
With an upper-level trough in the central CONUS continuing to track
eastward, the southwest CONUS will fall under a ridge during Day 2.
While surface high pressure will also weaken with the departing of
the upper-level trough, an inverted surface trough will remain in
place cross California, maintaining a modest pressure gradient
(though not as strong as previous days). With offshore flow being
continuous across the area, low-level air is expected to remain
quite dry, with very dry fuels in place that will continue to
promote potential for fire spread/growth.

...Southern California...
With at least a moderate pressure gradient established across
California, relatively strong offshore flow will again be a concern
across the southern California Foothills, especially during the
morning hours. Latest model guidance suggests 20-30 mph sustained
east-northeasterly winds will be likely during the morning hours,
accompanied by critically low RH in two distinct areas, with the
first area being the San Gabriel Mountain vicinity and the second
being along the San Jacinto and Laguna Mountain Ranges. In addition,
localized extremely critical conditions (over 30 mph winds with the
critical RH) may occur for brief periods of time over these same
areas, but the brevity and spatially constricted nature of these
conditions precludes an extremely critical delineation. From the
afternoon to the end of the period, a gradual weakening trend in
wind speeds are expected, with elevated to critical conditions
persisting, as critically low RH and very dry fuels will continue to
support wildfire spread.

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

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