SHORT RANGE OUTLOOK
(Through The Next 72 Hours)
Tropics No Longer An Influence In North America (As Lee Is Now Cold-Core And Moving Out Of The Maritime Provinces)
UQAM Meteocentre (3)
University Of Wisconsin Weather Server (3)
College Of DuPage Weather Laboratory
It is a bit of a surprise that what was once Hurricane Lee ended up not making any important alterations in the general USA weather pattern. While Lee did transition to a cold core entity, and helped to consolidate the 500MB trough complex over the eastern two-thirds of the continent. The upper air configuration is essentially the same as was seen in early summer across the continent. Hot air has been suppressed into Texas and Mexico, but there are no important cold advection mechanisms present. There likely will be a frontal wave that triggers thunderstorms across the Eastern Seaboard on Sunday into Monday. An upper level disturbance could also set off convection in the Great Lakes, Ohio valley and Appalachia. But what follows is essentially a vast quiet zone, with mild/warm temperatures to the right of the Rocky Mountains. No well-defined tropical systems are predicted to impact the lower 48 states during the new week.
Heat Ridge Rebuild In Mexico As Cool Air Fills In Across The West
When I look at the synoptic charts that show numerical model forecasts across North America, I am struck by the similarity to the weather pattern of this past June. Namely the presence of a bubble heat ridge across Mexico that occasionally expands into Texas. That would imply occasional surges of hot air into the south central states, with the worst of the hot air covering the Desert Regions, West and South Texas.Thunderstorms may develop on a scattered basis across the central High Plains, then drift either in singular fashion or clustered into Oklahoma, N TX and Arkansas and Louisiana. Cool air will reach the Pacific Northwest and the Great Lakes, New England. Overall this is what one would call a temperate configuration, with the only exception being in the southwest and south central states. Nothing major will happen until the Gulf of Alaska Low makes its move through the interior of the continent.