Good day everyone!
The Storm Prediction Center (SPC), Norman OK. has indicated a MODERATE risk of Severe Thunderstorms across parts of THE CENTRAL PLAINS AND MID-MS VALLEY…
There is a SLIGHT risk of Severe Thunderstorms surrounding the moderate risk FROM THE SRN HIGH PLAINS TO THE OH VALLEY…
SPC SEVERE WEATHER SUMMARY:
SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS PORTIONS OF THE CENTRAL PLAINS TO THE OHIO VALLEY. GREATEST CONCENTRATION OF SEVERE SHOULD EXTEND FROM NORTHERN KANSAS INTO SOUTHEASTERN NEBRASKA AND MUCH OF IOWA. VERY LARGE HAIL AND TORNADOES ARE POSSIBLE.
Based on my analysis of F5 DATA Severe Weather Software, utilizing output from the RAP, GFS, and NAM – WRF models, the NAM – WRF stands out better in accordance with the SPC products…however a blend of these three models despite very subtle differences appears to be accurate as well.
The analysis this morning indicates forecast severe weather indices in line with SPC parameters also matching the latest run of the SPC SREF model, and 12Z soundings from around the risk areas. The following maps, based on these data tend to indicate the best significant probability for tornadoes to occur within the outlined areas, in which supercells capable of producing EF2 – EF3 Tornadoes, and possibly some isolated EF4 – EF5 COULD initiate at approximately 4:00 p.m. CDT and into the early evening hours. This activity as noted in the SPC discussion, will depend on timing, and extent of ample moisture to initiate the supercells.
LISTED SELECT INDICES (SIGTOR AREA)
LIFTED INDEX = -6 to -8
SWEAT INDEX = 400 – 525
EHI = 3 to 6
SRH = 250 – 400+
SBCAPE = 2000 – 3000 (TORNADO THREAT AREA) 2500 – 3500 (MODERATE RISK AREA / SOUTH SLIGHT RISK AREA)
Albeit these areas are outlined I am not willing to rule out tornadic activity in the entire moderate risk area, and possibly into Oklahoma (as a precautionary measure). I believe at the moment, based on analysis, the primary threat of tornadoes will lie in the 30% hail outline, but more prominent within the 45% / hatched hail area.
The GREATEST probability for the occurrence of severe thunderstorms should lie within both risk areas, within the hatched area of the hail probability map.
For the portion of Nebraska and Iowa that may be under the gun, this has the potential to be a DANGEROUS situation. PLEASE REVIEW YOUR TORNADO ACTION PLANS…IF A TORNADO WARNING IS ISSUED…PLEASE SEEK IMMEDIATE SHELTER.
The following maps and graphics are linked for you to receive current severe weather information and NWS Statements and Warnings.
Happy Mothers Day to all the Moms…They are a significant part in our lives!
T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST / SEVERE WEATHER SPECIALIST
MEMBER WEST CENTRAL FLORIDA AMS
OFFICIAL SKYWARN SPOTTER (ADVANCED)