A rather locked-in jet stream pattern will keep the temperature pattern across the Lower 48 very similar over the next 1 to 2 weeks. An unusually deep trough over the western US, reaching the Baja California peninsula, is being triggered by a large ridge over Alaska. Downstream of that results in a ridge of high pressure over the eastern US, providing above average temperatures. In some of the highest of elevations of the northern mountains in the West, snow has been reported next week, but as a more substantial surface low pressure develops early-next week, a more widespread snow storm could be possible across the intermountain West and northern Plains thanks to the cold air in place.
This Thursday, the nation will literally be divided by 2 different air masses. Across the interior Northwest, northern and central Plains, and upper Midwest, it will be quite chilly and definitely fall-like. High temperatures will generally be in the 40s and 50s — even a few locations will struggle to get out of the 30s — which is nearly 35 degrees below average. Many locations in the Plains will likely break their record low maximum temperature for the day. The rest of the West will be cooler than average, but it will not be as significant with highs around 5 to 15 degrees below their typically high temperature for this time of the year.
Meanwhile to the south and east, temperatures will be above average, and even record-breaking at a few spots in the Southeast. High temperatures will be up to 20 degrees above average this Thursday, especially along the East Coast. Temperatures in the Northeast and Ohio River Valley will mainly be in the 70s and 80s while the Mid-Atlantic and South soar to around 90 degrees.
Temperatures will fluctuate into next week as different storms allowing for varying temperatures. On Friday, temperatures will not be as cold as on Thursday in the Plains, but highs in the 30s, 40s, and 50s will still be dealt with. In fact, across much of the Northern Tier, conditions will be below normal with highs generally in the 40s, 50s, and 60s. The West will also remain on the cool side, but temperatures will vary greatly by elevation. Across the southern Plains through the Southeast and points south, temperatures will remain above average on Friday with highs remaining near 90 degrees. Florida will be quite toasty with temperatures getting into the low to mid 90s.
Now this weekend, we’ll see a new push of cooler air move in, allowing for temperatures of up to 30 degrees below average to return tot he Plains. This time, however, the cool air will reach as far south as the Texas Panhandle. These below normal temperatures will reach as far east as the upper Midwest. To the west, it will be a cool, fall-like weekend while to the east it will feel more likely summer across most areas. Temperatures will be most significantly above average in the Ohio River Valley with temperatures in the 80s to near 90. Elsewhere, the Northeast will warm up to the 60s and 70s by Sunday while the 80s and 90s remain dominant across the Southeast.
Expect this overall pattern to persist through at least most of next week.