U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus01 kwns 250557 
Storm Prediction Center ac 250556 

Day 1 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
1256 am CDT Monday may 25 2015 

Valid 251200z - 261200z 

..there is an enh risk of severe thunderstorms today across parts of central 
into northeast Texas... 

..there is a slight risk of severe thunderstorms across surrounding areas of the 
Southern Plains and adjacent portions of the lower Mississippi 

..there is a slight risk of severe thunderstorms late this afternoon and evening 
across parts of the north Central Plains and middle Missouri Valley... 

..there is a marginal risk of severe thunderstorms across much of the remainder of 
the southern and Central Plains...and a corridor extending across 
the middle Missouri Valley into the Great Lakes region... 

Severe thunderstorms are likely today into tonight across much of 
central and eastern Texas into parts of the lower Mississippi 
Valley...as well as across parts of the Central Plains into the 
middle Missouri Valley. Strongest storms will be capable of 
producing large hail and potentially damaging wind gusts. A few 
tornadoes are also possible. 

Subtropical ridging appears likely to remain prominent along 
Atlantic coastal areas through this period. Models do indicate that 
upper flow across the western into central U.S. May begin to 
deamplify a bit...but broad upper troughing is forecast to 
persist...with a number of significant embedded short wave 
perturbations. Several of these will continue to progress east of 
The Rockies...within southwesterly middle/upper flow across the 
plains...Mississippi/Ohio valleys...and Great Lakes region...above a 
persistent southerly return flow. 

This includes one impulse which is expected to pivot northeast of 
the middle/lower Missouri Valley...through the upper Midwest early 
today...before becoming absorbed within increasingly confluent flow 
across and northeast of the Great Lakes region. Upstream...the 
remnants of a compact...but significant...mid-level circulation /now 
progressing into southwest Texas/ are expected to turn northeastward 
across the Southern Plains Red River valley during the day today. 
Guidance indicates that it will then continue through the lower 
Missouri Valley tonight...just ahead of the remnants of the closed 
low now beginning to progress east of the Front Range of The 

..Southern Plains... 
Models generally indicate that a 30-50 knots Lower/Middle tropospheric jet 
will accompany the impulse emerging from the southwest. This 
feature appears likely to nose north/northeast of The Big Bend 
region after 12z this morning. Associated forcing for 
ascent...coupled with returning moisture beneath at least modestly 
steep middle-level lapse rates...may already be in the process of 
supporting vigorous convective development across parts of the Texas 
South Plains and Edwards Plateau. This activity is expected to 
continue...gradually increasing in coverage and intensity while 
developing east northeastward through early afternoon...as inflow 
becomes increasingly rooted in a destabilizing boundary layer. 

The risk for large hail appears the primary severe threat initially. 
Eventually...a gradual consolidation of convection and associated 
outflow is expected to lead to evolution of an increasingly 
organized forward propagating convective system. Although ambient 
low-level wind fields may be initially modest...at least some 
intensification during the day...coupled with cold pool 
strengthening...may contribute to an increasing risk for potentially 
damaging wind gusts. Given the seasonably moist boundary layer 
/characterized by surface dew points near 70f/...mesovortices 
developing along the gust front may be accompanied by the risk for 
tornadoes or locally enhanced surface gusts as activity spreads 
toward the arklatex region and Sabine valley through early evening. 

In the wake of this initial convective activity...additional 
strong/severe storm development appears possible during the late 
afternoon and evening along the dryline across the Panhandle region 
into west central Texas. This should be more widely scattered in 
nature...but may include discrete supercells. 

..Central Plains into the middle Missouri Valley... 
Low-level moisture along/ahead of an increasingly better defined 
surface frontal zone will be more limited than across the Southern 
Plains. But...the northeastward advection of a plume of steep 
middle-level lapse rates is expected to contribute to moderately large 
cape by late afternoon. Storms may initiate first near the 
dryline...on the nose of stronger surface heating across north 
central Kansas...where vertical shear should be sufficient for 
supercells. Thereafter...a more substantive increase in storm 
development along the front...east northeastward across the middle 
Missouri Valley...is expected to await better forcing associated 
with impulse progressing east of the Front Range. This may not be 
until the 26/00-03z time frame...but the environment should still be 
conducive to the development of supercells...perhaps an organizing 
storm cluster or two. Large hail...damaging wind gusts and a couple 
of tornadoes all appear possible. 

.Kerr/picca.. 05/25/2015 

Mesoscale Discussion

acus11 kwns 250419 
sels mesoscale discussion 
Storm Prediction Center mesoscale discussion 250419 

Mesoscale discussion 0754 
National Weather Service Storm Prediction Center Norman OK 
1119 PM CDT sun may 24 2015 

Areas affected...southwest Kansas 

Concerning...Tornado Watch 206... 

Valid 250419z - 250515z 

The severe weather threat for Tornado Watch 206 continues. 

Summary...a tornado threat /potentially strong/ may continue through 
at least 05z/midnight CDT across southwest Kansas including areas 
near/west of Dodge City. Severe hail/wind will otherwise remain 

Discussion...ahead of an eastward-moving convective line...a 
persistent discrete supercell with history of producing tornadoes 
continues to slowly move northeastward across far southern Gray 
County as of 1115 PM CDT/0415z. While overall supercell intensity 
may be Post-Peak and environmental cinh has increased over the past 
1-2 hours...supercell internal dynamical processes and relatively 
strong low-level shear per Dodge City WSR-88D vwp data could 
maintain a supercell tornado threat toward the Dodge City area 
through at least the 05z/midnight CDT time frame...if not beyond. 
Otherwise...some severe wind/hail may remain a concern with the 
eastward-moving convective line...with it likely to eventually 
overtake the aforementioned supercell. 

.Guyer.. 05/25/2015 

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


Latitude...Lon 37920083 38120025 38239984 38039946 37159963 36960098