Worst of the storms offshore, evening round of rain expected

Wednesday has been declared a Weather Authority Alert Day


JACKSONVILLE, Fla. – Today was a Weather Authority Alert Day because of  rounds of severe storms that contained damaging wind gusts in excess of 60 mph, up to 1 inch hail, isolated tornadoes, lightning, and heavy rainfall.  We were in a pattern of heavy downpours since the beginning of the week and the heavy rainfall lead to localized flooding at times, particularly near McCoy's creek and in Mayport.  Rain is beneficial for our area experiencing drought but the severe storm threat and possibility for tornadoes was the worrisome aspect of today's weather. 

A weak tornado/waterspout was reported by Flagler County Emergency Management:

At 8:54am, just south of Summer Haven in St. Johns County a tornado was spotted. It  was extremely brief and weak. In the time it took to be reported over the radio it was over. It began as waterspout in the intracoastal waterway, then passed across a barrier island and into ocean, then dissipated.  No damage. NWS and St. Johns advised. It should be emphasized that this was a VERY WEAK tornado.

Here is a compilation of area rainfall totals from the National Weather Service: 

Location                     Amount   
3 N Olustee                  4.99 in  
4 NW Interlachen             4.24 in  
2 NNW Tallyrand              3.59 in  
5 W Maxville                 3.48 in  
3 NE Yulee                   3.44 in 
4 SE Fort White              2.94 in 
3 ENE Oceanway               2.84 in    
8 N Florahome                2.83 in       
6 SSE Alachua                2.76 in   
5 SE Alachua                 2.67 in  
1 SSE Ortega                 2.61 in         
5 SSE Brooker                2.54 in     
1 N Yulee                    2.51 in  
Div Forestry                 2.48 in   
5 NNW Blackshear             2.41 in        
Sanderson 4.9 NNW            2.34 in       
6 NE Lake Geneva             2.32 in      
1 SE Ortega                  2.25 in  
1 SW Interlachen             2.25 in   
4 NNE Mandarin               2.24 in      
1 SSE Baxley                 2.21 in      
3 WSW Vilano Beach           2.16 in         
2 NW University Of Florida   2.10 in        
1 NNW Mannville              2.08 in 
Micanopy 8.5 W               2.06 in 
3 ENE Florahome              2.06 in  
5 WNW Newberry               2.01 in         
5 ENE Lake Geneva            1.98 in          
3 W Talbot Island            1.96 in       
Lake Geneva                  1.95 in        
1 SW Ortega                  1.91 in          
2 NNE Unf                    1.90 in         
9 N Florahome                1.87 in         
3 W Bellair                  1.84 in  
3 W Normandy                 1.83 in        
4 SW Baxley                  1.80 in 
3 WSW Kingsland              1.79 in        
1 SSW Trenton                1.78 in    
2 WNW Micanopy               1.78 in          
5 WNW Ocala Airport          1.71 in         
2 NNE Micanopy               1.67 in        
1 E Normandy                 1.58 in          
1 SW San Pablo               1.56 in         
3 S Boys Estate              1.56 in      
1 N Glen Saint Mary          1.56 in        
Little Satilla River Near Of 1.45 in      
4 NE Florahome               1.44 in        
2 ENE Tallyrand              1.43 in        
Jacksonville 6.7 WSW         1.41 in   
3 SSW Folkston               1.41 in  
3 S Glen Saint Mary          1.40 in 
7 NNW Taylor                 1.38 in   
Suwannee River At Us Hwy 441 1.34 in 
2 WSW Picolata               1.34 in   
2 SSW Fort Caroline          1.33 in  
5 ESE Thalmann               1.33 in  
2 SSE Arlington              1.25 in       
St Augustine Airport         1.25 in       
5 SSW High Springs           1.23 in         
Jacksonville 8.9 ENE         1.23 in      
2 ENE Screven                1.20 in 
Fargo 2ne                    1.19 in 
2 NNW Bakersville            1.19 in      
3 SSE San Marco              1.18 in        
Live Oak                     1.17 in  
4 E Suwannee River Station   1.15 in          
Pridgen                      1.15 in     
Lake City 7.9 SSW            1.14 in        
Waycross                     1.12 in        
2 SSW Anthony                1.12 in        
2 W Deenwood                 1.10 in        
2 WNW San Pablo              1.08 in       
Satilla River At Us 17 At Wo 1.06 in         
1 SSE Arlington              1.05 in       
Neptune Beach                1.04 in          
1 WNW Alachua                1.00 in       
2 S Arlington                0.99 in  
Jacksonville Nas             0.98 in       
2 NW Bellair                 0.96 in  
1 NNW Ortega                 0.95 in  
2 WNW Green Cove Springs     0.91 in        
Hastings 3 Mi Wnw            0.90 in 
Satilla River At Ga 158 Near 0.90 in          
1 S Jacksonville Heigh       0.86 in    
Atkinson 1wsw                0.85 in       
Homerville 5n                0.85 in 
University Of Florida        0.84 in       
1 WNW Ortega                 0.84 in          
Hedges 0.3 ESE               0.84 in         
1 ENE Jacksonville Heigh     0.83 in         
Bacon County Airport         0.82 in      
1 WNW Steven Foster State Pa 0.82 in          
University Of Florida        0.81 in  
Alapaha River At Hwy 94      0.81 in         
4 WNW Newberry               0.75 in       
Mayport Naval Station        0.75 in          
Jennings 6.7 S               0.72 in         
Jesup 10.0 NNW               0.72 in         
5 NNW Alachua                0.70 in         
5 NW Doctortown              0.70 in          
1 SSE Lumber City            0.70 in         
Craig Municipal Airport      0.67 in       
1 SE Gainesville             0.67 in        
Penney Farms                 0.67 in        
Gainesville Regional Airport 0.67 in         
Jacksonville Intl Airport    0.65 in    
3 SE Yulee                   0.64 in         
4 SW Unf                     0.63 in  
2 NNE Oceanway               0.61 in         
3 ESE Sanderson              0.60 in         
5 NNW White Springs          0.60 in        
Fernandina Beach             0.58 in        
3 ENE Kingsland              0.51 in         
White Springs                0.50 in        
Jacksonville 12.0 SSE        0.50 in      
3 ENE Mandarin               0.49 in        
Fernandina Beach             0.49 in         
3 NW Middleburg              0.48 in          
Orange Park 4.8 SSW          0.46 in     
3 WNW Orange Mills           0.46 in        
Doctortown                   0.45 in        
4 ESE Alachua                0.44 in        
Steven Foster State Park     0.43 in    
2 NE Kingsland               0.43 in    
White Springs 1.0 SSE        0.42 in     
1 W Mcintosh                 0.42 in      
Wtr Tr Plt                   0.42 in      
5 WNW Newberry               0.41 in         
3 WNW Manor                  0.41 in          
Trenton 4.0 NW               0.40 in          
1 WNW Saint Augustine Beach  0.39 in          
1 S Bellair                  0.38 in     
Pearson 3.5 NE               0.38 in          
1 SW Saint Simons            0.38 in       
4 WSW Switzerland            0.37 in        
3 WNW Ocklawaha              0.36 in          
6 SSE Brooker                0.36 in      
5 NW Salt Springs            0.32 in       
High Springs 3.2 SW          0.31 in          
1 NNE Weirsdale              0.30 in         
2 NW Gainesville             0.28 in          
3 N Flemington               0.28 in         
Observations are collected from a variety of sources with varying
equipment and exposures. We thank all volunteer weather observers
for their dedication. Not all data listed are considered official.

At 12:53p.m. today a thunderstorm wind gust of 42 mph was measured at NAS Jax. At 1:29p.m. the airport in Ocala measured a 41mph thunderstorm wind gust. 




The NWS Storm Prediction Center has issued a Severe Thunderstorm Watch for portions of the Florida peninsula including Clay, Putnam, St Johns, and Flagler counties & Coastal Waters effective this Wednesday afternoon and evening from 245 PM until 1100 PM.

   Primary threats include:
     Isolated damaging wind gusts to 70 mph possible
     Isolated large hail events to 1.5 inches in diameter possible
     A tornado or two possible

   SUMMARY...Thunderstorms developing along and ahead of a convective outflow boundary now advancing inland off the Gulf coast are expected to increase in coverage and intensity across the interior and eastern peninsula through this evening.  Strongest activity may be accompanied by severe wind gusts and hail, with some risk of a  tornado or two, mainly near Atlantic coastal areas. The severe thunderstorm watch area is approximately along and 60 statute miles east and west of a line from 5 miles west of St Augustine FL to 20 miles southeast of Fort Meyers FL. 

The National Weather Service in Jacksonville has issued a Flood Warning for Central Nassau County in northeastern Florida, Duval County in northeastern Florida until 4:15 p.m. At 1:17p.m, Doppler radar and automated rain gauges indicated thunderstorms with heavy rain over the area. The rain will cause flooding. Rainfall at the Jacksonville International Airport was 3.32 inches since around 11 am this morning. Additional rainfall of 1 to 2 inches are possible. Some locations that will experience flooding include: Jacksonville, Fernandina Beach, Callahan, Jacksonville International Arpt, Arlington, Yulee, Neptune Beach, Cisco Gardens, San Pablo and Craig Field.

The National Weather Service in Jacksonville has issued a Flood Advisory for Bradford County in northern Florida, Central St. Johns County in northeastern Florida, Southern Baker County in northeastern Florida, Union County in northern Florida, Clay County in northeastern Florida, Southern Duval County in northeastern Florida until 4:45 PM. At 1:51 PM, Doppler radar indicated heavy rain due to thunderstorms. This will cause minor flooding in the advisory area. Up to two inches of rain have already fallen.  Some locations that will experience flooding include Saint Augustine, Orange Park, Green Cove Springs, Starke, Lake Butler, Raiford, Ponte Vedra Beach, Unf, Mandarin and Fruit Cove.

The storms began late Tuesday night over central southern Georgia and the Florida Panhandle as a line of severe storms moved over the First Coast.  The storms were ongoing and widespread near Jacksonville through mid morning Wednesday.

Afternoon heating will fire up additional storms during the afternoon.

The cause of the severe threat is a significant upper level shortwave trough digging deep into the southeast. This makes layered winds through the atmosphere turn and increase in speed supporting organized storm structures capable of damaging winds and perhaps a couple of tornadoes. 

The day will be marked with winds blowing 25-30 mph even beyond the reach of storms.

The National Weather Service office in Jacksonville says:

A few waves of showers and thunderstorms expected on Wednesday and Wednesday night.  During the pre-dawn hours early Wednesday morning, showers and thunderstorms will push into the Suwannee Valley of NE Florida. Then push through the rest of NE FL during the early morning commute Wednesday morning.  Strong to severe thunderstorms anticipated with each wave Wednesday and Wednesday night.  The Storm Prediction Center has the entire region in a Slight Risk for Severe Weather  Southwest winds at the surface will increase at 15 to 25 mph with some higher gusts.  Wind gusts of in excess of 60 mph possible.  Hail up to the size of quarters possible.  An isolated tornado cannot be ruled out.

A cold front will push into Florida Thursday morning increasing the moisture supply.

Many areas in the South will pick up 2 to 4 inches of rainfall through Thursday morning. However, where thunderstorm clusters stall or move too slowly, higher amounts are expected.

The best chance of greater than 3 inches of rain will occur in a swath along I-75 near Gainesville to Lake City. Many places will see 2 inches of rainfall into Duval with totals around 1.5 inces closer to the coast in Flagler and St. Johns counties.

The good news is that the West Mims fire has not increased in activity and crews continue to increase containment of the smoldering swamp fire.

Lightning can spark additional fires which is the mechanism that started the wildfire initially. 

Dry weather returns Thursday afternoon in time for the Memorial Day Weekend.

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