U.S. Severe Weather Forecast (Previsión convectiva)

día tres

acus01 kwns 240049 
Storm Prediction Center ac 240048 

Day 1 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
0748 PM CDT sun Apr 23 2017 

Valid 240100z - 241200z 

..there is a slight risk of severe thunderstorms centered over 

..there is a marginal risk of severe thunderstorms from portions of 
southern Georgia to extreme southern NC... 

Strong thunderstorms may still impact parts of Georgia and the 
Carolinas tonight, accompanied by at least some risk for severe 
weather. This includes a possibility for a couple of tornadoes near 
a frontal zone across the Piedmont and coastal plain of South 


Early evening water vapor imagery depicts the center of a pronounced 
upper low over the northwestern tip of Alabama in line with latest 
short-range model guidance. This feature will dig into Georgia late 
tonight as strongest flow aloft has yet to round the base of the 
trough. 00z soundings from jax and chs depict modest mid-level 
lapse rates/deep-layer shear and ongoing convection supports this 
being somewhat disorganized and not particularly strong. As the 
trough approaches Georgia/SC late tonight, shear profiles should increase 
such that organized sustained updrafts will be more likely, 
especially within stronger low-level warm advection where low level jet is 
focused. Will maintain slight risk for severe storms centered over SC 
where a few tornadoes may develop if sustained supercells evolve. 

.Darrow.. 04/24/2017 


Mesoscale Discussion

acus11 kwns 240232 
sels mesoscale discussion 
Storm Prediction Center mesoscale discussion 240232 

Mesoscale discussion 0552 
National Weather Service Storm Prediction Center Norman OK 
0932 PM CDT sun Apr 23 2017 

Areas affected...southeast Georgia...central/eastern SC 

Concerning...severe potential...watch unlikely 

Valid 240232z - 240500z 

Probability of watch issuance...20 percent 

Summary...thunderstorms are expected to persist into late tonight, 
especially across portions of South Carolina. The strongest cells 
will be capable of locally damaging wind and perhaps a tornado or 
two. Watch issuance is considered unlikely at this time. 

Discussion...thunderstorms have recently increased in coverage and 
intensity across portions of eastern Georgia into west-central SC. This 
increase occurred in conjunction with a collision of the 
westward-moving sea breeze and an eastward-moving outflow boundary 
emanating from earlier convection over Georgia. The resulting composite 
boundary extends southward from a weak surface low over eastern GA, 
with another nearly-stationary boundary extending eastward from the 
low across central SC. 

A few cells have exhibited weak rotation across portions of 
west-central SC in Aiken and Barnwell counties, though these are 
likely slightly elevated and up to now have not appeared to pose an 
appreciable severe risk. Cells further south have shown less 
organization, but as they advance eastward into a somewhat more 
unstable airmass across the coastal plain of SC, some increase in 
intensity is possible with a risk of locally damaging wind in the 
short term. 

Later this evening, a modest increase in the low-level jet is 
anticipated in response to a well-defined upper low that will move 
slowly east-southeastward into Georgia. As this occurs, cells that are 
able to interact with the frontal boundary (which may move slowly 
northward as a warm front with time) may pose a threat of a brief 
tornado or two, though widespread convection and relatively weak 
deep-layer shear will likely keep the severe threat relatively 
limited. While a low-end severe threat will exist for much of the 
night, the magnitude of the threat at any particular location and 
time is currently expected to remain too limited for watch issuance. 

.Dean/guyer.. 04/24/2017 

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


Latitude...Lon 32718163 33238157 33728142 34058052 33997956 33827892 
33227913 32787973 32368044 31878113 31948167 32278171