Back to back cold fronts charging through the region this weekend will deposit quite the chilly air mass Monday into Tuesday. Highs from 60-65 will be manageable, even refreshing, but overnight lows in the 30s in our colder areas could spell trouble for some plants.
The GFS model projects freezing low temperatures Tuesday morning along and west of a line from around Columbia to Rockville to Dulles to Manassas.
The European model is a little warmer placing the freezing line west of the Blue Ridge.
I tend to favor the European model’s warmer solution, but even this less frosty scenario would allow for lows in the mid-to-upper 30s in our colder suburbs west and northwest of the city. So, I would not be surprised to see some frost advisories issued Monday night.
Historically, it’s not that unusual to have low temperatures this cold this late in the season. Dulles Airport has experienced a freeze in May in 6 out of the last 30 years. The latest freeze on record at Dulles occurred on May 22, 2002 when the mercury plunged to 31 degrees. The most recent May freeze at Dulles was on May 3, 2005.
Alex Liggitt, a meteorologist at WJLA, wrote a nice blog post on this same topic, with this piece of sound gardening advice, pertinent primarily for Washingtonians who live west of the beltway:
Mike McGrath, WTOP’s Garden Editor, tells Doug Hill and myself that it is best to typically wait until after May 15th to plant outside. This year that is no joke!
Inside the beltway and towards the Chesapeake Bay, it’s probably fine to put in your plants by late April in most years.
We’ll keep you posted on any frost or freeze watches/advisories/warnings posted in the coming days. Again, Monday night is the night temperatures are projected to fall the most.