WGN-TV Weather Team and Tom Skilling
February 2024 highs topped 40 degrees again Wednesday—something which has occurred each of the month’s opening 14 days despite normal highs in the low and mid-30s each of those days
- February 2024 to-date remains the 3rd-warmest such period of the past 153 years now averaging more than 12 degrees above normal
- The period is also 6.4-degrees warmer than Feb. 1-14 a year ago
- METEOROLOGICAL/CLIMATOLOGICAL SUMMER SEASON continues 7th warmest of the past 153 years averaging 6.1 degrees ABOVE NORMAL.
- Underscoring the extended nature of the milder than normal temps, the past year ranks 3rd-warmest since 1871 with a 2.5 degree full-year surplus.
It’s been 55 days since our shortest day of the year back on Dec. 21 and the period of daylight each day continues lengthening.
Wednesday saw 2 minutes 25 seconds more daylight than yesterday—and Chicagoans bask in an hour and 24 minutes more daylight than we saw back on Dec 21. By the end of February this leap year—Feb 29 (which is just 15 days away)—we will see an additional 40 minutes of daylight.
Mild temps hold Thursday; cold air moves in Friday
It will be a mild Thursday amid gusty winds which may build close to 40 mph at times, but on Friday, the southern flank of a cold air mass to our north sweeps into the area. A disturbance is to carry some snow across southern sections of the area then as the 2-day cold snap hits. The chill will be of moderate intensity, compared to the arctic blast we suffered for 9 days back in January. But temps Friday and Saturday will hold to the 30s—10 to 15 degrees off recent highs in the 40s with wind chills as low as single-digits Saturday morning and no higher than the 20s both Friday and Saturday afternoon.
A fairly expeditious temp rebound follows with readings topping 40 Sunday afternoon and surging to near 50 Monday and into the low 50s Tuesday and Wednesday before a second brief cool air incursion takes temps down on Thursday, Friday, and Saturday next week.
Even so, TEMPS THIS WEEK, while averaging 6 degrees cooler than last week, are still likely to post a 4-degree surplus by week’s end—and NEXT WEEK is likely to warm an average of 40 degrees and come in nearly 6 degrees above normal.
More California rains arriving on the Pineapple Express
The powerhouse mid-Pacific 225 mph jet stream level winds continue their trek toward the West Coast along with what looks to be another series of wet, windy ATMOSPHERIC RIVER/PINEAPPLE EXPRESS STORMS expected to sweep heavy rains into central California and areas north on the Pacific Coast by and during the coming weekend—then settling south to impact much of the remainder of the California coast after that. Heavy mountain snows are again expected in the Sierra. It’s storms like this that send milder air into the Lower 48 and hold prolonged outbreaks of arctic air at bay over a wide swath of the Plains and Midwest.
This is an 11-day NWS BLENDED MODEL ESTIMATE OF POTENTIAL WATER EQUIVALENT PRECIP which covers the period through 6am CST a week from this coming Sunday.
El Niños often intensify West Coast storms, and recent analysis shows a notable increase in Trans-Pacific and Southern jet stream winds
While the current El Niño is weakening, it remains potent, potentially fueling another wave of enhanced storms in the coming week. El Niños often act to supercharge West Coast storms—and this analysis of the increased strength of TRANS-PACIFIC AND SOUTHERN JET STREAM WINDS since Dec. 1 shows how much stronger southern or SUB-TROPICAL JET STREAM WINDS have been, which help guide storms and ATMOSPHERIC RIVERS into the West Coast.
THE POWERHOUSE eastbound JET STREAM LEVEL WINDS moving from the central toward the eastern Pacific: