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Storm Prediction Center Forecast


RSS Mesoscale Discussions from Storm Prediction Center

SPC - No watches are valid as of Thu Jan 17 16:34:01 UTC 2019

No watches are valid as of Thu Jan 17 16:34:01 UTC 2019.


SPC - No MDs are in effect as of Thu Jan 17 16:34:01 UTC 2019

No Mesoscale Discussions are in effect as of Thu Jan 17 16:34:01 UTC 2019.


SPC Jan 17, 2019 1300 UTC Day 1 Convective Outlook

SPC 1300Z Day 1 Outlook
      
Day 1 Outlook Image
Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0648 AM CST Thu Jan 17 2019

Valid 171300Z - 181200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not expected across the Lower 48 states
through tonight.

...Western States...
A progressive flow regime will continue over the contiguous U.S.
through tonight. A strong mid/upper-level speed max will move from
northern CA toward the Southwestern Deserts as an associated trough
amplifies over the Great Basin. Ample moisture for the season along
with increasingly cold temperatures aloft will support a relatively
broad corridor of isolated thunderstorm potential, particularly from
northern CA/southwest OR into NV and parts of UT/northern AZ. 

Although buoyancy will be minimal coincident with seasonal
temperatures, various forecast soundings across parts of
central/eastern NV into western UT suggest some potential for a
couple of stronger storms this afternoon and evening near the
advancing cold front. Convectively enhanced wind gusts could occur
with this activity in the presence of 45-50 kt winds near the top of
the boundary layer.

...Mid-South/Tennessee Valley...
A weak/low-amplitude shortwave trough and preceding warm advection
will support eastward-shifting isolated elevated thunderstorms
during the day.

..Guyer/Kerr.. 01/17/2019

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SPC Jan 17, 2019 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
1029 AM CST Thu Jan 17 2019

Valid 171630Z - 181200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS EASTERN
NV/WESTERN UT...

...SUMMARY...
Strong to isolated severe wind gusts will be possible with isolated
thunderstorms across parts of eastern Nevada into western Utah
during the late afternoon and early evening.

...Eastern NV and Western UT...
Guidance differs greatly with the degree and eastern extent of
boundary-layer heating with the NAM substantially cooler than the
RAP, given a pervasive swath of ongoing cloudiness. However,
mid-level drying yielding clearing is evident in satellite imagery
across western NV and this should shift eastward into the afternoon.
In conjunction with mid-level cold-air advection, the setup should
foster increasing destabilization during the afternoon via delayed
boundary-layer heating and lapse rates aloft becoming very steep. 

Mid-level DCVA associated with the portion of the shortwave trough
shifting from northern CA into the Great Basin and convergence along
a cold front should yield a broken band of showers with embedded
thunderstorms by late afternoon from the NV/UT/ID border area
south-southwest into east-central NV. 30-40 kt effective shear could
support modestly organized convective structures. Where inverted-v
thermodynamic profiles can develop, strong to isolated severe wind
gusts may occur as activity spreads east before waning this evening.

..Grams/Squitieri.. 01/17/2019

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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
0935 AM CST Thu Jan 17 2019

Valid 171700Z - 181200Z

...NO CRITICAL AREAS...

Forecast remains on track and please see the discussion below for
more details.

..Nauslar.. 01/17/2019

.PREV DISCUSSION... /ISSUED 0148 AM CST Thu Jan 17 2019/

...Synopsis...
A shortwave ridge over the Four Corners will shift east and
deamplify today. This will result in the development of a weak
surface trough across the southern High Plains, though the pressure
gradient will be modest. In addition to the weak surface pressure
gradient, midlevel westerly flow will remain light through 00z, and
surface winds generally will be less than 15 mph. Though winds will
be weak, a very dry airmass will persist, aided in part by weak
downslope flow. As a result, RH values will fall into the 20-30
percent range across parts of eastern NM into western TX. While
locally elevated fire weather conditions may occur on brief/spotty
basis, unfavorable fuel conditions, with ERC values below normal,
will limit overall threat. Further east, dry conditions will persist
across parts of northern into central FL and RH values in the 30-40
percent range are expected once again. However, wind speeds less
than 10 mph will largely preclude fire weather threat.

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

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