severe weather watch and a look ahead to boston marathon...

[WXBUFFJIM]

Good evening everyone. We'll mention severe storm potential in a minute. But we must mention what could be a real serious story, which could unfold for the Boston Marathon on Monday April 19th, 2004. The warmest Boston Marathon ever was accomplished on the same date, April 19th, 1976 during the tail end of a 3-4 day April heat wave. During parts of the race in 1976, temperatures were known to reach into the 90s in the Boston area. Providence hit 98 degrees on April 19th, 1976. Of the 1898 starters in the 1976 Boston marathon, 40% of the runners exited the race prematurely with symptoms of heat exhaustion.

This years race could possibly have over 20,000 enteries, 10 times that of 1976. This race will probably be run on one of the warmest marathons ever in Boston Marathon history. Heat related illnesses for both runners and spectators maybe a real concern on Monday as high temps are expected to reach 85 degrees in Boston. The only saving grace for Boston is if a sea breeze keeps temperatures in the immeidate Boston area much cooler than the projected high os 85. If temps reach into the mid to upper 80s on Monday, this will be one of the warmest Boston Marathons ever. A public information statement could be issued by the Taunton, MA NWS office as we draw closer to this event to strongly address the possible life threatening dangers from this potential heatwave.

Meanwhile the focus further west is not only heat, but thunderstorms, some of which will likely be severe in the next few hours. There are already severe thunderstorm warnings in effect for northern Ohio to affect areas just south of Cleveland and Sandusky, Ohio. Large hail and high wind are possible with this broke line of storms in northern Ohio throughout the evening.

Meanwhile across north central Iowa, a warm front is beginning to slowly move to the north as a cyclogenesis begins to develop across the north central Plains. A developing low level jet will feed in moisture from the south and energize this round of thunderstorms throughout the evening. The only problem for the next hour or two is there is too much capping in place. However once the cap breaks, severe thunderstorms should just explode and rapid intensification of supercell storms can be expected across north central Iowa within the next two hours or so. very large hail, damaging winds, and a few tornadoes are likely in this area. A severe weather watch could be needed in this region in the next 1-2 hours.

More severe weather could affect northern Iowa, southern Minnesota, and southern Wisconsin through the early evening hours with large hail, damaging wind, and a few tornadoes yet this evening.

More severe weather is expected in this region tomorrow with the potential for a more widespread severe weather outbreak tomorrow across southern Minnesota and northern Iowa.

After this severe weather episode, the focus will then shift towards a potentially dangerous and life threatening Boston Marathon. Running in temps in the mid to upper 80s for 26.2 miles is not a pretty thing for persons this far north. Usually temps are in the 50s in Boston during a typical marathon. The saving grace is if a seabreeze kicks into the immediate Boston area. Let's hope for that!!!

Jim

[Guest]

However once the cap breaks, severe thunderstorms should just explode and rapid intensification of supercell storms can be expected across north central Iowa within the next two hours or so.

Those CAPES are sure screaming across Iowa/extreme Eastern Nebraska at the moment. It will not be too long before we begin to see the storms pop. Looking at the mesoanalysis on the SPC website (visible satellite) , I notice some ACCAS development around the Sioux City area

[ssom04]

Looking at the mesoanalysis on the SPC website (visible satellite) , I notice some ACCAS development around the Sioux City area

I saw the samething, I think it will be to dry here with a dew point of 36 but Nws is still calling for severe storms tonight....I'll have a better chance tomorrow when the dew points are in the 60s[/quote]

[WXBUFFJIM]

Also the cold pool, which is over California will only serve to enhance instability in the midwest tomorrow. You think tonight maybe bad, tomorrow afternoon and evening could be even worse with tornadoes a real possibility from northern Iowa to south central Minnesota.

Jim