WEATHERAmerica Newsletter, Sunday, August 9, 2026; SHORT And MEDIUM RANGE OUTLOOKS

[Larry Cosgrove]

SHORT RANGE OUTLOOK

(Through The Next 72 Hours)

 

Cool Canada Vs. Warm/Hot USA Alignment; Active Thunderstorm Threats Midwest, Great Lakes, Northeast

METEOBLUE

PivotalWeather.Com (3)

ECMWF

College Of DuPage Weather Laboratory

When the arc of hot, dry air from Mexico and Texas meets a warm/moist fetch from the Gulf of Mexico and surges of cool values out of central/eastern Canada, Much of the Midwest, Great Lakes and the Northeast will be bedeviled by rounds of intense thunderstorms, While diurnal/seabreeze convection will occasionally visit in an area from East Texas through the Dxiie states, severe weather will probably be concentrated in the Interstate 64, 70, 80 and 90 corridors. The monsoonal fetch may produce orographic precipitation, but much of the West looks hot and dry. Cool advection should cover most of southern Canada, and occasionally get pulled down to about 40 N Latitude. The main concern in this pattern is the chance for an derecho or discrete severe weather/supercells, which most of the numerical model guidance points to in a bracket from SD, MN, and IA into Virginia and the Mid-Atlantic.

 

MEDIUM RANGE OUTLOOK

(Four To Ten Days From Now)

 

The Pattern Holds; Southern Half Of The USA Continues To Broil Under A Very Steady Siege Of Hot Air

METEOBLUE

TrueWx.Com (4)

UQAM Meteocentre (4)

ECMWF (4)

College Of DuPage Weather Laboratory

If you thought that the established North America weather pattern was going to go away anytime soon....guess again!

There is blocking setting up over Alaska and the Yukon Territory, and Greenland as well. Now if this were winter, every snow and ice enthusiast would be jumping for joy. But when amplification of the jet stream occurs in the second half of summer, there is still a lot of room for heat surges and subtropical highs over the southern half of the USA. The storm track over  the northern Pacific Basin will eject shortwaves west to east across southernmost Canada. Some of the hotter air may reach the Ontario Peninsula and St. Lawrence Valley (to the right of approaching surface low pressure). But the main impacts continue to look convective through the end of the month, with dangers for severe weather from the northern/central Rocky Mountains into the Missouri Valley, Great Lakes, Mid-Atlantic and New England states.

And again if you live along and below 40 N Latitude, especially in Texas, Oklahoma, and Kansas, count on daily displays of heat and humidity.