* Freeze warning midnight until 9 a.m. west of Intestate 95 *

9:30 p.m. update: The freeze warning was expanded eastward to include all of Montgomery and Howard counties, and much of Fairfax and Prince William counties. Basically, all areas west of Interstate 95 are now under the warning.

Earlier post

Yep, that’s a freeze warning. (National Weather Service)

Update: The National Weather Service transitioned the freeze watch into a freeze warning, and dropped the near-north and west suburbs in the process.

If you live in the farnorth or west suburbs, there’s a chance you could wake up to a frosty car and grass on Wednesday morning.

Behind Monday morning’s cold front, temperatures are plummeting. Flurries have been spotted in the northern Washington suburbs, and there is a freeze warning in effect for northern Montgomery, Loudoun, Frederick and north Howard counties for Wednesday morning, when temperatures could dip below 32 degrees.

What happened to spring?

Jason Samenow wrote that winter was over on April 10. That’s still the case, despite the chill in the air.

Even though “average” April high temperatures range from 62 at the beginning of the month to 71 at the end, temperatures vary widely. Real-life weather is seldom average; it’s made up of high and low extremes that, when you do the math, average out to a nice, round number like 67 degrees, which is the average temperature for April 17 in Washington.

We started declaring the start of spring in 2014, and we use two simple rules to do it:

  • No accumulating snow in long-range forecasts that could remain on the ground for 12 hours or more.
  • No cold weather — highs in the 40s (or colder) and lows below freezing in Washington for more than 48 hours.

Despite how cold it might feel, we’re still pretty far away from the winter threshold as defined above. The high temperature should reach 50 degrees at National this afternoon, and by tomorrow afternoon it will be back in the mid-60s.