That's April for you. Forecasters out at Sterling Tuesday night are warning residents across the northern tier of Maryland counties to expect frost overnight as skies clear at temperatures dip into the upper 30s for only the seventh time this month. Western Maryland could see lows in the 20s.
Frost advisories were posted from Harford County west to Washington County. There were freeze warnings farther west in Allegany County. The Frost Advisories include Howard and Montgomery counties, but not Baltimore City or the southern portions of Baltimore County. They mean that sensitive outdoor plants may freeze if they're not covered.
The cold threat won't last long. Daytime highs will climb this week into the 70s, and to the 80s by the weekend, if the forecast holds up. We may even reach the upper 80s by Sunday or Monday. Overnight lows will rebound into the 60s by the weekend.
The warming trend comes courtesy of a building region of high pressure later this week. Once the center moves by and we get into a southwest or westerly flow around the backside of the clockwise circulation, temperatures will climb. The heat will likely break with a cold front Monday, accompanied by showers and thunderstorms.
(NOAA Photo Library)