U.S. Severe Weather Forecast (Convective Outlook)

Day Three

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Storm Prediction Center ac 181942 

Day 1 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
0142 PM CST Mon Feb 18 2019 

Valid 182000z - 191200z 

..no severe thunderstorm areas forecast... 

thunderstorms remain possible over The Four Corners region today, as 
well as areas from southeast Texas to the lower Mississippi River 
valley late tonight. 

..20z update... 
No changes have been made to the ongoing forecast. 

.Gleason.. 02/18/2019 

Previous discussion... /issued 1030 am CST Mon Feb 18 2019/ 

..Four Corners area... 
An upper trough will continue to dig southeastward today over the 
southwest deserts toward northwest Mexico. DPVA/upper jet exit 
region-related forcing for ascent and diurnally steep lapse rates 
will allow for the possibility of lightning-producing convection 
across The Four Corners vicinity this afternoon. 

..southeast Texas to lower Mississippi Valley tonight... 
Showers along with isolated/embedded thunderstorms are expected to 
develop and increase particularly overnight into early Tuesday. This 
will be as increasing warm advection/moisture transport occurs 
coincident with the elevated frontal zone. Weak buoyancy and 
modestly steep mid-level lapse rates should be sufficient for some 
elevated thunderstorms, which will generally be based between 
850-700 mb per forecast soundings. Although shear through the 
cloud-bearing layer will be strong, elevated buoyancy should be weak 
enough such that meaningful hail is unlikely. 


Mesoscale Discussion

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sels mesoscale discussion 
Storm Prediction Center mesoscale discussion 180727 

Mesoscale discussion 0107 
National Weather Service Storm Prediction Center Norman OK 
0127 am CST Mon Feb 18 2019 

Areas affected...northern New Jersey...lower Hudson Valley...Long 
Island...much of CT 

Concerning...winter mixed precipitation 

Valid 180727z - 181130z 

Summary...mixed winter precipitation is expected to continue from 
northern New Jersey across the lower Hudson Valley and into CT for the next 
few hours. 

Discussion...recent regional radar imagery has shown a modest 
increase in precipitation intensity across the region. Observations 
continue to show a transition zone from rain to freezing rain to 
snow extending from northern New Jersey across the lower Hudson Valley and 
into eastern CT. Expectation is for light to moderate precipitation 
to persist across this region for the next few hours as 
southwesterly flow aloft continues to support warm-air advection. 

Those areas currently experiencing rain (i.E. Long island) and 
freezing rain (i.E. Northern New Jersey and lower Hudson valley) will likely 
continue to experience those precipitation types as surface 
temperatures remain steady and low to mid-level temperatures 
increase slightly. Areas experiencing snow will likely see a 
transition towards more mixed precipitation as mid-level 
temperatures continue to gradually warm but surface temperatures 
remain unchanged. Freezing rain rates around 0.02"-0.05" per hour 
are possible. 

.Mosier.. 02/18/2019 

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


Latitude...Lon 41647416 41747379 41827331 41887250 41757201 41597176 
41357168 41047203 40677327 40587404 40567444 40587468 
40647490 40797508 41057502 41267483 41647416