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Storm Prediction Center Forecast


RSS Mesoscale Discussions from Storm Prediction Center

SPC - No watches are valid as of Fri Nov 15 07:20:04 UTC 2019

No watches are valid as of Fri Nov 15 07:20:04 UTC 2019.


SPC - No MDs are in effect as of Fri Nov 15 07:20:04 UTC 2019

No Mesoscale Discussions are in effect as of Fri Nov 15 07:20:04 UTC 2019.


SPC Nov 15, 2019 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
1139 PM CST Thu Nov 14 2019

Valid 151200Z - 161200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Scattered thunderstorms are possible Friday across parts of the
Southeast.

...Southeastern US...

Strong short-wave trough will dig southeast across the Mid-South and
off the GA coast by the end of the period. This will force northern
Gulf short-wave trough to eject quickly across the FL Peninsula by
18z. As a result, stronger low-level convergence should refocus off
the Atlantic coast as surface low becomes better defined offshore.
Observed/forecast buoyancy is not particularly noteworthy over the
FL Peninsula thus any thunderstorms that spread onshore should
struggle to attain meaningful intensity. With time, low-level warm
advection should drive thunderstorm development along/near warm
front draped just off the Southeast coast. Despite the strengthening
wind fields, poor instability will preclude severe probs this
period.

..Darrow/Cook.. 11/15/2019

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SPC Nov 15, 2019 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
1220 AM CST Fri Nov 15 2019

Valid 161200Z - 171200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
A few weak thunderstorms are possible over eastern North Carolina on
Saturday. Otherwise, stable conditions will prevail over the Lower
48.

...Synopsis and Discussion...
A shortwave trough will move off the coastal Southeast with a
surface low deepening off the NC/SC coast. As moisture wraps around
the low, elevated instability will develop, with a few thunderstorms
possible across parts of eastern NC. The surface air mass over the
region should remain too cool for any surface-based severe threat,
with the strongest storms well offshore.

Elsewhere, high pressure will maintain dry and stable conditions
over the remainder of the CONUS.

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

..Jewell.. 11/15/2019

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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
0113 AM CST Fri Nov 15 2019

Valid 151200Z - 161200Z

...Synopsis...
A progressive, amplified synoptic pattern will remain in place
across the Lower 48, with shortwave troughs located across the
Southeast and also just offshore west of California and Baja
California.  Between these two systems, low-amplitude ridging aloft
along the Continental Divide will shift quickly to the east through
the forecast period, reaching the Ohio Valley by 12Z Saturday.  At
the surface, a weak trough will persist across coastal areas of
California, and high pressure will build into portions of the
Pacific Northwest late in the day.  The resultant pressure gradient
will be enough to cause offshore flow to develop tonight and elevate
fire weather conditions.  Elsewhere, only locally elevated fire
weather is expected across the Texas Panhandle and vicinity today as
lee surface troughing locally enhances surface wind fields in that
area.

...Southern California...
An elevated fire weather delineation has been introduced for this
update.  Later tonight, strengthening surface flow will commence
within typical terrain-favored areas, with 15-25 mph northerly flow
and 15-30% RH values becoming common.  The region has also remained
rain free over the past 90+ days, with dry fuels supporting a risk
of fire spread.  These conditions will likely continue into
D2/Saturday with poor overnight recovery and continued offshore
gradient in place.

..Cook.. 11/15/2019

...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
0114 AM CST Fri Nov 15 2019

Valid 161200Z - 171200Z

...Synopsis...
Fire-weather concerns on D2/Saturday will be centered around an
offshore gradient in southern California, which should develop in
earnest as high pressure builds into the Great Basin.  Farther east,
lee troughing/surface cyclogenesis will commence across the central
High Plains, which should spread dry and breezy conditions across
eastern Colorado/western Kansas and vicinity.  Meanwhile, cool
conditions will prevail west of a coastal low that will organize
over the Gulf Stream throughout the forecast period.

...Southern California...
Offshore surface flow will strengthen during the day in response to
a strengthening surface high in the Great Basin.  Areas of 15-25 mph
easterly/northeasterly surface flow will become common, with some
areas experiencing higher gusts.  Meanwhile, poor overnight recovery
and diurnal surface heating/drying will result in near- to
sub-critical (10-15%) RH values areawide during peak heating hours. 
Over time, the surface pressure gradient will strengthen further
late D2/Saturday into early D3/Sunday morning, and may require
critical highlights to be introduced - especially if surface flow is
stronger than anticipated.  Overnight recoveries will remain poor
D2/Saturday night.

..Cook.. 11/15/2019

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

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