SPC - No watches are valid as of Mon Apr 23 08:17:01 UTC 2018

No watches are valid as of Mon Apr 23 08:17:01 UTC 2018.


SPC - No MDs are in effect as of Mon Apr 23 08:17:01 UTC 2018

No Mesoscale Discussions are in effect as of Mon Apr 23 08:17:01 UTC 2018.


SPC Apr 23, 2018 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
1235 AM CDT Mon Apr 23 2018

Valid 231200Z - 241200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM EASTERN
GEORGIA INTO CENTRAL SOUTH CAROLINA...

...SUMMARY...
A few strong to severe storms are possible across parts of Georgia
and South Carolina. Isolated thunderstorms will also be possible
over parts of the High Plains.

...Synopsis and Discussion...
An upper low will drift eastward from the lower MS Valley toward the
TN and OH Valleys, with a weak surface trough extending from western
TN into GA by late afternoon. A warm front will lift north across
eastern GA into central SC, with mid 60s F dewpoints to the south.
Meanwhile, a cold front will extend from the AL/GA border southward
across the western FL Panhandle.

Precipitation and clouds are expected across the Marginal Risk area
during the morning, driven by low-level warm advection and a 40+ kt
southeasterly low-level jet. Most of the early storms are expected
to be north of the warm front, with little severe threat.

Later in the day, strong heating over GA will result in steep
low-level lapse rates and perhaps 1000 J/kg MUCAPE, with scattered
afternoon storms likely. Wind profiles will be mainly unidirectional
west of the warm front, with cellular activity producing marginal
hail or wind. A few storms could become supercells near the warm
front where low-level SRH will be greatest, but may quickly become
elevated as storm motions will be to the northeast. Still, a low
threat of a tornado exists, along with the marginal hail and wind.

..Jewell/Gleason.. 04/23/2018

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SPC Apr 23, 2018 0600 UTC Day 2 Convective Outlook

SPC 0600Z Day 2 Outlook
      
Day 2 Outlook Image
Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1253 AM CDT Mon Apr 23 2018

Valid 241200Z - 251200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHWEST
TX INTO FAR SOUTHWEST OK...

...SUMMARY...
Isolated severe thunderstorms are possible from southwest Texas
northeastward into far southwest Oklahoma.

...Synopsis...
Mature cyclone centered over middle TN/central KY at the beginning
of the period is expected to move northeastward across the central
Appalachians. Surface low beneath the mid/upper cyclone will
continue to fill while a secondary low develops farther east and
moves northeastward across the Carolinas. Some thunderstorms are
possible in the vicinity of the secondary low as well as across FL
as the surface trough moves through. 

Farther west, a shortwave trough will move southeastward into the
central Plains, encouraging a southward surge of a cold continental
airmass into the southern Plains. A warm and deeply mixed airmass
ahead of the cold front over the southern High Plains will likely
support isolated to widely scattered thunderstorms.

...Southern High Plains...
Southerly winds are anticipated across the region ahead of the
approaching cold front but only modest low-level moisture (i.e.
dewpoints in the low 50s) is expected to reach the area. Even with
this meager low-level moisture, destabilization is still expected as
the boundary layer mixes to near 700 mb and surface temperatures
climb into the low to mid 80s. This destabilization will support
isolated thunderstorms along the front. Thunderstorms are also
possible ahead of front as forcing for ascent from the shortwave
trough moving through the central Plains reaches the region.
Low-level flow is not expected to be particularly strong but
mid-level flow will gradually increase during the late afternoon and
evening, supporting the potential for updraft organization and an
isolated severe storm or two. 

...Carolinas...
Predominantly elevated thunderstorms will likely be ongoing at the
beginning of the period across the region. A few surface-based
storms are possible within the warm sector confined to the coastal
regions. Limited spatial extent for strong thunderstorms as well as
the displacement of the stronger flow northward suggest any severe
threat will be too isolated to merit any severe probabilities with
this outlook. 

...Central/Southern FL Peninsula...
Scattered thunderstorms are possible on both sides of a weakening
frontal zone moving slowly southward across the region. Generally
weak flow and poor lapse rates should keep the severe probabilities
below 5%.

..Mosier.. 04/23/2018

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SPC Apr 23, 2018 0730 UTC Day 3 Severe Thunderstorm Outlook

SPC 0730Z Day 3 Outlook
      
Day 3 Outlook Image
Day 3 Convective Outlook  
NWS Storm Prediction Center Norman OK
0227 AM CDT Mon Apr 23 2018

Valid 251200Z - 261200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Isolated thunderstorms are anticipated over portions of the southern
Plains as well as over portions of the Mid-Atlantic states on
Wednesday.

...Synopsis...
A series of shortwave troughs will traverse the broad upper
troughing anticipated east of the Rockies on Wednesday. The
progression of these shortwaves coupled with a building upper ridge
across the Intermountain West is expected to result in a general
amplification of the upper pattern by 12Z Thursday. Surface pattern
will feature a high progressing southward across the southern Plains
in the wake of a cold front sweeping across the region.

Isolated elevated thunderstorms are possible from the Permian Basin
into north Texas early in the period with additional development
possible along the front during the afternoon and evening. Limited
instability is currently expected to preclude severe thunderstorms.

Farther east, isolated thunderstorms are possible near the surface
low and attendant trough associated with a weakening cyclone.
Anticipated low coverage and minimal instability will temper severe
potential.

..Mosier.. 04/23/2018

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SPC Apr 23, 2018 Day 4-8 Severe Weather Outlook

Day 4-8 Outlook
      
Day 4-8 Outlook Image
Day 4-8 Convective Outlook  
NWS Storm Prediction Center Norman OK
0314 AM CDT Mon Apr 23 2018

Valid 261200Z - 011200Z

...DISCUSSION...
Medium-range guidance is in better agreement regarding the
large-scale upper pattern through the weekend. General consensus is
for an eastward progression of both the mean upper trough covering
the central and eastern CONUS at the beginning of the period (i.e.
12Z Thursday) and the western CONUS ridging. Once this occurs, the
upper pattern will become more favorable for moisture return across
the Plains and MS Valley. Most recent model suite shows decent
moisture return beginning across the Plains on D7/Sunday and
D8/Monday. However, forecast confidence is low given the significant
run-to-run and model-to-model consistency within the guidance noted
over the past few runs.

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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
0125 AM CDT Mon Apr 23 2018

Valid 231200Z - 241200Z

...NO CRITICAL AREAS...

...Synopsis...
An upper trough over the Pacific Northwest and northern Great Basin
will develop eastward across the northern High Plains today.
Meanwhile, a vertically stacked cyclone should move slowly eastward
across the TN Valley through the period. At the surface, warm/dry
conditions with related lowered RH values will be relegated to
mainly parts of the Southwest this afternoon. Generally light winds
are expected where fuels remain receptive across this region, which
will limit concerns for elevated/critical conditions.

..Gleason.. 04/23/2018

...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
0126 AM CDT Mon Apr 23 2018

Valid 241200Z - 251200Z

...NO CRITICAL AREAS...

...Synopsis...
A positively tilted upper trough is forecast to migrate southward
from the northern to central Plains by Tuesday evening as a separate
upper low moves slowly eastward from the TN Valley towards the
Mid-Atlantic. At the surface, a cold front will sweep southward
across parts of the central and southern Plains. Areas of lowered RH
values will likely be confined to portions of the Southwest into far
west TX Tuesday afternoon. With light surface winds forecast across
these areas, neither elevated nor critical conditions are expected
across the CONUS on Day 2/Tuesday.

..Gleason.. 04/23/2018

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

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