Beautiful Easter/Passover weekend with (except for markedly cooler lakeshore and beach air temps) the warmest weekend of 2023 ahead.
It’s cooler near the lake season and easterly lake breezes off the 42-deg lake waters mean immediate shoreline locations are likely to warm no higher than the mid to upper 40s Saturday while inland high temps surge into the low to mid 60s.
Sunday is to see high surge several degrees higher inland with lakeshore and beach temps rising to the mid to upper 50s as a south/southeast wind flow locks in. SSE winds travel over less water than easterly winds which means they have less time to be cooled by their interaction with the chilly lake water.
But the real warmth takes hold next week with a 70-deg high predicted Monday—then summer level upper 70s to low 80s due Tuesday, Wednesday and Thursday with no rain or storminess.
Back to back 80-deg or warmer daytime highs appear a distinct possibility Wednesday and Thursday which, if true, would mark the first consecutive 80-deg or warmer highs to occur here since way back on Sept 20-21 when highs in Chicago reached 86 and 85-deg respectively.
Daily highs Tuesday through Friday are predicted to average 13 to 25-deg above normal if current forecast trends verify. Those are summer level temps. Humidities will remain fairly low and dry air cools at night. But it also warms very efficiently by day.
A huge dome of warm air is to build over the Midwest then become essentially lock in place between a wet low pressure system on the Gulf coast and cool air pools and upper low pressure systems in the Northwest U.S. and Canadian Maritimes. This is known as a “Rex Block”–and when such a blocking pattern develops, weather systems slow. In the case of next week’s weather, this locks warm, rain-free and generously sunny weather in place.
Next week appears likely to average 14-deg warmer than this week and 15-deg above normal. That’s an eye-catching temp departure which will be allow a noticeable change to 2023’s warmest temp levels.
HERE’S MY LATEST FRIDAY CHICAGO METRO FORECAST (4/7/2023):
TONIGHT: Scattered clouds by morning, chilly. Low 35—but upper 20s colder inland locations.
SATURDAY: Becoming mostly sunny and milder—but with cool lake breezes into area beaches and shoreline locations. High 62—but only 47 along Lake Michigan.
SATURDAY NIGHT: Scattered clouds, not quite as cool. Low 41—mid 30s inland.
EASTER SUNDAY: Partly sunny, milder inland but with cooler lake breezes again along Lake Michigan. High 66—but mid 50s lakeshore.
MONDAY: Partly sunny and warmer. High 70.
TUESDAY, WEDNESDAY and THURSDAY: Mostly sunny and noticeably warmer with the warmest temps of 2023 to date. Breezy late mornings and afternoons. High Tuesday 76; Wednesday’s high 80 and Thursday’s high 83.
FRIDAY: Partly sunny, continued warm—but with possible localized afternoon lake breezes cooling shoreline locations modestly. High 77.
SATURDAY: Partly cloudy, temps remain well above normal but southeasterly lake breezes will cool the shoreline. High 75—60s lakeshore.