Forecast for June 24, 2008

Today there is a slight risk of severe thunderstorms for areas of Southeastern Saskatchewan and Southwestern Manitoba. With CAPE values approaching 1500 J/kg. in areas, with deep layer shear values forecast to be around 20-40 kts, along with some modest helicity values, severe thunderstorms may develop given a good trigger. With shear values in that range, a threat for supercells that may produce large hail, damaging winds, and an isolated tornado may occur.

One concern I have that may lead to no severe weather is the forecasted strong CINH, or cap. If the forecasted cap turns out weaker, or if storms can break it, this risk may be upgraded to a moderate risk tomorrow. Stay tuned for more details on this.

There is a threat for non-severe thunderstorms in Alberta in areas off the foothills, with a greater threat in NW Alberta. Lack of shear and lower SBCAPES in the forecast by the models are the main reasons for this lower threat. If anything changes, I will let you know in an updated forecast.

Included also is a severe weather threat map, along with a tornado threat map for tomorrow (June 24, 2008)

Jon
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MAPS:

Severe Threat

Tornado Threat


NEXT UPDATE BY 17Z/12PM CDT JUNE 24/08