Huge 45° temperature surge in just two days

Huge temperature swings are a part of any Chicago spring season. The warming strength of the sun was demonstrated Wednesday, only the fourth day since March 1 to produce 100% of the area’s possible sunshine. In just nine hours area thermometer observers watched one of the three latest occurring 27° morning lows on record in over 135 years of official weather records evaporate at the hands of a 37° temperature surge. Afternoon readings peaked 18° above Tuesday’s 46° high at a seasonable 64°. Even warmer readings are predicted Thursday. Converging winds ahead of a southbound Wisconsin cold front ought to induce a bit of compressional warming—a process which occurs as any gas is squeezed or compressed. Should Thursday’s 72° high verify, it would make the 11th reading at or above 70° this month—already the 7th warmest April since 1871.
-Tom Skilling