Good day everyone!

Tropical Cyclone formation is not expected during the next 5 – 7 days.

Again, regarding issuance of tropical updates and severe weather updates, severe weather updates will be posted for SLIGHT risk or greater outlines. Once we begin seeing probabilities for possible tropical development, or we get a developing system, the tropical weather update will take precedence.

The Storm Prediction Center indicates an ENHANCED risk for severe thunderstorms for Wed., and Thu., and a SLIGHT risk for Fri., and Sat. The following graphics are linked to their outlooks:
DAY 2 OUTLOOK:

DAY 3 OUTLOOK:

DAY 4 – 8 OUTLOOK: 

IF 1300Z SPC DAY 1 outlook graphics are utilized, please check the SPC site for any updates to the outline risks when they are issued.  The next update is issued at 1630Z (12:30 p.m. EDT) 

SPC CURRENT DAY1 SEVERE WEATHER OUTLOOK
The Storm Prediction Center (SPC) has issued an ENHANCED risk for severe thunderstorms in the current DAY1 Outlook: ACROSS THE NORTHERN AND CENTRAL PLAINS…

…SPC SUMMARY…
Numerous severe thunderstorms with a potential for 60-80 mph winds with locally higher gusts, along with tornadoes (some potentially strong), and large to very large hail are expected across the northern and central Plains this afternoon and tonight. Severe wind gusts and large hail will also be possible from north-central and west-central Kansas southwestward into the Texas Panhandle.
1630Z SPC DAY 1 SEVERE THUNDERSTORM OUTLOOK (LINKED FOR OUTLOOK TEXT)

TORNADO PROBABILITY

Probability of a tornado within 25 miles of a point.  Hatched area: a 10% or greater probability of  EF2 – EF5 tornadoes within 25 miles of a point
HAIL PROBABILITY

Probability of one inch diameter hail or larger within 25 miles of a point. Hatched area: a 10% or greater probability of 2.0 inch diameter or larger hail within 25 miles of a point 
DAMAGING THUNDERSTORM WIND PROBABILITY

Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point.  Hatched area: a 10% or greater probability of 65 kt+ winds within 25 miles of a point

CSU – MLP DAY 1 AND 2 FORECAST PROBABILITIES (CLICK FOR LARGER IMAGE)

NSSL ML DAY 1 PROBABILITY


CSU – MLP 6 PANEL PROBABILITIES DAY 3 – DAY 8 FORECAST (CLICK FOR LARGER IMAGE)




DAY 1 PROBABILITY CONVERSION TABLE


SPC DISCUSSION EXCERPT:
…Central and Northern Plains…
Thunderstorms are expected to form near the front/dryline by mid/late afternoon, initially spanning the west-central Dakotas southward into western Nebraska. Some semi-discrete storms including supercells may also form farther east within the warm sector, enhanced as the mid-level jet phases with a significantly strengthening low-level jet primarily focused across eastern North Dakota/northeast South Dakota. Aside from large hail, a few tornadoes are expected, some of which could be strong especially during the early/mid-afternoon hours. Over time and farther west, strong low-level convergence near the instability axis will result in a relatively rapid transition to linear mode with multiple linear clusters/possible MCS expected to develop by evening. The severe MCS will move eastward across the central and eastern Dakotas, with damaging wind and some hail/tornado potential continuing eastward tonight toward Minnesota/part of Iowa.

Aside from North Dakota/northern South Dakota and northwest Minnesota, another supercell/tornado-favorable zone could materialize by evening farther southeast from southeast South Dakota into eastern Nebraska and western Iowa/southwest Minnesota. Mid-level temperatures will be a bit warmer and storm coverage/certainty will likely be lesser across this region. However, a rather favorable and potentially volatile environment will exist as a secondary low-level jet branch increases and interfaces with an effective warm frontal zone this evening, with initial intense supercells plausible if/where storms develop.

The following maps are from NADOCAST for tornado and hail probabilities.  Click each image for a larger view.  
12Z NADOCAST TORNADO PROBABILITY

12Z NADOCAST SIGTOR PROBABILITY

12Z NADOCAST HAIL PROBABILITY

12Z NADOCAST SIGHAIL PROBABILITY

Based on my analysis this morning, the current forecast severe weather indices call for a very unstable to extremely unstable atmosphere within the ENHANCED risk and the 30% HATCHED HAIL OUTLINE. The main severe risk as of analysis this morning is the possibility of severe damaging thunderstorm winds / gusts, possibly to 80 mph, LARGE to VERY LARGE hail, and the possibility of a TORNADOES.  The tornado risk is at 5% – 10% over the ENHANCED risk and HATCHED TORNADO outline. While any tornadoes that occur should be weak (EF0 – EF1), the HATCHED probability suggests the possibility of an EF2, possibly isolated EF3 with any of the strongest cells

If there is a lack of sufficient 0 – 1 km SRH, effective (EFF.) SRH will be used in calculation of tornadic EHI.  From research: (Effective Layer SRH: Recent research suggests using “effective layer” SRH (usually 1250-2250m AGL) as a superior substitute for 0-1 km SRH, as it better represents the inflow layer for supercells).

EHI INDICES are for the guidelines listed above.  Listed indices will always pertain to the area(s) located within the highest SPC risk outlines, based mainly on SBCAPE indices, and / or regarding a higher tornado potential, should multiple severe risk areas appear in the SPC forecast.  Although certain indices may appear stronger on a forecast map, given the lack of other indices does not contribute to the overall severe risk.  Bear in mind, MAXIMUM indices recorded below are for the time of peak intensity.  Some indices meanings are posted below the indices themselves, and the NWS page containing a more extensive explanation can be accessed further on in the synopsis.

The following were the forecast parameters and indices analyzed this morning within the ENHANCED risk outline and the HATCHED TORNADO OUTLINE:  
SBCAPE: 3000 – 5000 j/kg-1              
MLCAPE: 2500 – 4500 j/kg-1                  
MUCAPE: 3000 – 5000 j/kg-1
SRH 0 -1 km: 110 – 120 m2/s2       
SRH 0 -3 km: 225 – 300 m2/s2     
SRH EFFECTIVE: 150 – 200 m2/s2      
L. I.: -9 to -12                                            
SCP: 3 – 28
STP: 0.4 – 3.3
0 -6 km SHEAR: 30 kts – 50 kts                  
EFF. SHEAR: 30 kts – 40 kts                        
MID LEVEL LAPSE RATE: 7.5C – 9.0C
DEWPOINT: 69F – 73F                                   
SUPERCELL EHI : 6.3 – 6.5
TORNADIC EHI : 2.6 – 3.1                       
TOTAL TOTALS INDEX: 57C       
K INDEX: 28C to 40C                                          
SWEAT INDEX: 635 – 695            
THOMPSON INDEX: 37 to 52  
CRAVEN – BROOKS INDEX: 20,000 – 65,000

About West Central Florida Hurricane and Severe Weather Forecast Center

I am a Meteorologist, Hurricane Specialist and Severe Weather Specialist, providing hurricane forecasts during the Atlantic Hurricane Season, severe weather forecasts during and off season, as well as winter weather and coastal storm forecasts. I retired from the U.S. Coast Guard in July of 2001. Meteorology became my passion in high school, and I have continued my educational background in meteorology since 1996, when I undertook the study of Tropical Meteorology. While working toward my degree, I had to unexpectedly withdraw from college due to my oldest sons medical reasons. I do however, meet the educational criteria of the AMS to be recognized as a meteorologist. Studies include, but are not limited to the Navy Aerographers Mate course, Naval METOC meteorology course, Meteorology 2010 Sophomore level course while attending St. Petersburg College, Clearwater, FL., Basic Forecasting course for operational meteorologists from Rapid WX meteorology institute, a four month meteorological internship at FOX 13 News, and extensive research on numerous meteorological topics. I have been forecasting Tropical Weather (Tropical Storms and Hurricanes) since 1996, with my main clients at the time being three different Coast Guard Commands.