The two main features discussed in my last couple of blogs for the summer will continue the battle this week across the central and eastern part of the country.
Another impressive polar impulse diving south and phasing with a strong Pacific jet wind max over the northern part of the country, will bring a radical shift in the weather pattern late this week. This projected upper air development will give the boot to our present hot and steamy weather by surging a more comfortable air mass into the area late this week. Daytime high temperatures will fall off into the 70s to near 80. In the meantime however; waves of upper energy will ripple through the very unstable air mass over the region the next several days and act as the "match for the dynamite" in place. Strength of storm development will be determined by the dynamics of the atmosphere, instability available and to a lesser extent; timing of the storms. In addition, the risk of very heavy rains and local flooding will come with any of the rougher storms, especially when training over the same region.
Strong to severe thunderstorms are possible overnight Monday through early Thursday as the energy impulses push through the northern and eastern part of the country. Later in the week on Thursday; a strong cold front, spawned by the shift in the Polar jet will barrel toward the Great Lakes later Wednesday and clear through the region on Thursday.
An earlier model run during this past weekend /Sat-GFS/ intimated severe
squall-line development for later this week with even an argument for a derecho type
of system affecting several states. Since then, projections have backed
off some but still a few rounds of severe weather with damaging winds
are possible across much of the region.
Making weather fun while we all learn,
Bill Deedler -SEMI_WeatherHistorian
