U.S. Severe Weather Forecast (Convective Outlook)

Day Three

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Storm Prediction Center ac 270055 

Day 1 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
0655 PM CST Thursday Nov 26 2015 

Valid 270100z - 271200z 

..there is a marginal risk of severe thunderstorms across north-central Texas... 

a strong storm or two will remain possible mainly across parts of 
north-central Texas this evening...but organized severe 
thunderstorms are not expected. 

..Southern Plains... 
A closed/positive-tilt upper trough will remain centered over the 
Great Basin through tonight...while a strong cold front extending 
from far southeast Kansas to central/southwest OK and the Texas South 
Plains early this evening will continue a steady south-southeastward 
progression. Isolated thunderstorms will remain semi-focused 
near/just behind the south-southeast-moving cold front across the Southern 
Plains...while other embedded thunderstorms will remain possible 
this evening mainly across north-central Texas within a band of 
low-level confluence ahead of the cold front. 

With the bands of linearly organized convection across north-central 
Texas...a few bowing segments and transient/weak circulations will 
remain possible this evening within a highly sheared environment. 
Aided by weak southeasterly surface winds and a 40 knots southerly 
low-level jet...0-1 km srh is on the order of 200-300 m2/s2 as per 
the 00z Fort Worth sounding/recent WSR-88D vwp data. Even so...weak 
lapse rates and relatively cool boundary layer temperatures /upper 
60s f/ will otherwise hinder updraft vigor and limit the overall 
severe likelihood tonight. Reference mesoscale discussion 1995 for 
additional details. 

.Guyer.. 11/27/2015 


Mesoscale Discussion

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sels mesoscale discussion 
Storm Prediction Center mesoscale discussion 270118 

Mesoscale discussion 1996 
National Weather Service Storm Prediction Center Norman OK 
0718 PM CST Thursday Nov 26 2015 

Areas affected...portions of northestern nm...the Texas/OK panhandles...northwestern 
OK...much of Kansas...far southeastern Nebraska...northwestern MO...and southwestern Iowa 

Concerning...freezing rain 

Valid 270118z - 270715z 

Summary...ongoing light to moderate freezing rain with rates in 
excess of 0.05 inches per 3 hours will continue across much of Kansas 
into far southeastern Nebraska...northwestern MO...and southwestern Iowa through the evening. 
Additional freezing rain development appears likely across portions 
of northestern nm into the Texas/OK panhandles and northwestern OK over the next few 

Discussion...a broad area of light to moderate precipitation 
associated with a lead upper-level impulse and middle-level 
frontogenesis is depicted in recent radar imagery across much of Kansas 
and extending northeastward into southwestern Iowa. Per 01z surface observations...some of 
this precipitation is falling as freezing rain where surface 
temperatures have fallen at or below freezing behind a southward-moving cold 
front. A pronounced 9-10 degree c warm nose is centered around 850-800 
mb per 00z soundings from Topeka Kansas and Amarillo Texas along with a 
shallow near-surface sub-freezing layer. This suggests that freezing 
rain will remain the primary ptype for at least the next few 
hours...with sleet becoming an increasing possibility towards 07z as 
the sub-freezing layer near the surface increases in depth. 
Freezing-rain rates of 0.05-0.10 inch/hour remain possible... 
particularly in Kansas...southeastern Nebraska...northwestern MO...and southwestern Iowa where radar 
imagery shows reflectivity bands in excess of 35 dbz are occurring. 

Across portions of northestern nm...the Texas/OK panhandles...and northwestern 
OK...additional precipitation is forecast to develop through this 
evening as another upper-level impulse moves northeastward around an upper 
low centered over the Great Basin. With the surface freezing line 
advancing steadily southward across this area...this additional 
precipitation will likely be mainly freezing rain per the 00z 
sounding from Amarillo Texas and various forecast soundings through at 
least 05z. Beyond that time...there is an increasing chance for the 
freezing rain to transition to sleet as the warm nose aloft erodes 
and the depth of the near-surface sub-freezing layer increases. 

.Gleason.. 11/27/2015 

..please see www.Spc.NOAA.Gov for graphic product... 


Latitude...Lon 34510230 34140462 34590499 35700499 36960197 38040009 
38859878 40019678 40689580 41549485 41299397 40049482 
39059564 37779678 36409825 35230009 34510230