SPC - No watches are valid as of Thu Mar 21 17:53:02 UTC 2019

No watches are valid as of Thu Mar 21 17:53:02 UTC 2019.


No Mesoscale Discussions are in effect as of Thu Mar 21 17:53:02 UTC 2019.

SPC Mar 21, 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
1130 AM CDT Thu Mar 21 2019

Valid 211630Z - 221200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER A PORTION
OF CENTRAL THROUGH NORTHWEST NEW MEXICO AND FAR WEST TEXAS...

...SUMMARY...
Isolated, marginally severe wind gusts and hail are possible in the 
early afternoon near the Four Corners and then around early evening
over the Trans-Pecos of far west Texas.

...Northwest New Mexico region...

Satellite and radar imagery show a forced band of convection over
extreme northwest NM. This activity is associated with a
negative-tilt shortwave trough moving northeast near the Four
Corners area. Visible imagery show some cloud breaks downstream, and
diabatic heating of the surface layer should further destabilize the
atmosphere, though limited low-level moisture will limit MLCAPE to
200-400 J/kg. Given very steep mid-level lapse rates and at least
marginal instability in the presence of strong vertical shear, a few
storms might produce locally strong downdrafts and hail this
afternoon. 

...Trans-Pecos region of West Texas...

A few storms might develop over the mountains of northern Mexico
later this afternoon and spread northeast into far west TX by
evening. Low-level moisture with dewpoints in the 40s will likely
mix down into the 30s as low clouds erode, which will significantly
limit instability. Nevertheless a couple of locally strong wind
gusts will be possible with any high based convection as lapse rates
steepen, contributing to inverted-V boundary layers.

..Dial.. 03/21/2019

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SPC Mar 21, 2019 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
1229 PM CDT Thu Mar 21 2019

Valid 221200Z - 231200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTHERN HIGH PLAINS FRIDAY AFTERNOON AND EVENING...

...SUMMARY...
Isolated severe thunderstorms are possible across the southern High
Plains from Friday afternoon through early evening.

...Southern High Plains Vicinity...

A shortwave trough will shift eastward across the southern Rockies
to the Plains on Friday. Ahead of this feature, modest boundary
layer moisture will be transported north/northwest from the western
Gulf of Mexico. Surface dewpoints in the low 50s are forecast across
much of west TX into far eastern NM with decreasing values further
north toward southeast CO and southwest KS. Ongoing showers and
cloud cover will initially limit destabilization, but with as the
shortwave shifts eastward, cooling aloft will result in steepening
midlevel lapse rates and MLCAPE peaking around 1000 J/kg is possible
in a narrow corridor across the Marginal risk area. Strong height
falls during the afternoon and evening will result in a weak lee
trough across eastern CO/NM with a Pacific cold front shifting east
across the southern High Plains during the evening and overnight
hours. 

Shear profiles will be strongest/most favorable for
organized/rotating convection further north where backed low level
flow closer to the weak lee low will exist. However, moisture will
be marginal across this area and storms may be higher-based.
Additionally, hi-res guidance suggests line segments are most likely
as the Pacific front quickly shifts eastward and weak instability
limits stronger updraft potential. Convection may be able to remain
cellular a bit longer further south where forcing mechanisms will be
more subtle and instability/moisture modestly better. However, shear
profiles become weaker in the low levels. As a result, storms may
also be fewer with southward extent. Overall, steep midlevel lapse
rates coupled with modest instability/shear will result in at least
a marginal threat for hail and wind, and a tornado can not be ruled
out. 

As convection shifts eastward across the OK/TX Panhandles/TX South
Plains toward western OK overnight, severe threat should wane as
convection becomes elevated with time as the boundary layer
stabilizes with loss of heating. While steeper lapse rates do
overspread the Panhandles and western OK overnight, instability is
very weak and even small hail from elevated convection appears
unlikely.

...MAXIMUM RISK BY HAZARD...
Tornado:   2%     - Marginal
Wind:      5%     - Marginal
Hail:      5%     - Marginal

..Leitman.. 03/21/2019

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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
1145 AM CDT Thu Mar 21 2019

Valid 211700Z - 221200Z

No changes are needed to the ongoing outlook, with Elevated fire
weather conditions expected for a few hours this afternoon across
parts of southern/eastern GA and northern FL. While locally elevated
fire weather conditions are possible farther westward across
portions of the Florida Panhandle, the spotty/brief nature of
sustained wind speeds near 15 mph coupled with relatively marginal
fuel dryness for large fire starts precludes the expansion of the
Elevated fire weather area. See previous discussion below for more
information.

..Elliott.. 03/21/2019

.PREV DISCUSSION... /ISSUED 0200 AM CDT Thu Mar 21 2019/

...Synopsis...
An upper trough/low will continue to move slowly eastward across the
Southwest, Great Basin, and central Rockies today. A belt of strong
mid-level west-southwesterly flow will remain over much of southern
AZ/NM through the period. A separate upper trough will move across
the eastern CONUS through the day, with enhanced mid-level westerly
flow overspreading much of the Southeast. At the surface, a low will
develop northeastward along/near the Mid-Atlantic Coast. A weak
trailing cold front will move southeastward over parts of the
Carolinas and GA through the period.

...Portions of Southern/Eastern GA and Northern FL...
Westerly surface winds around 15 mph will likely occur in
conjunction with lowered RH values of 25-35% across parts of
southern/eastern GA and northern FL for a few hours this afternoon.
Although fuel dryness appears marginal to support large fire starts,
fine fuels are probably dry enough per latest guidance. Have
therefore introduced an elevated delineation for parts of this
region. The southern extent of the elevated area in northern FL has
been constrained by recent precipitation.

...Portions of the Southwest...
A small area of strong/gusty southerly surface winds will likely
overlap RH values below 20% across parts of southeastern AZ and
southwestern NM this afternoon. However, latest guidance continues
to depict a general lack of fuel receptiveness across this region.
So, an elevated area has not been included.

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

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