Baltimore goes from Isaias’ leftover showers to near-record October warmth and then to the coldest air of the fall in a single week. The National Weather Service forecasts a high near 84 degrees at BWI Marshall Airport on Wednesday, two degrees shy of the date’s record, followed by a Friday cold front that drops Saturday night’s low to around 38.
For anyone planning yard work, a game-day cookout or a weekend on the Chesapeake Bay, the timing of that front is the part of the forecast that matters most.
Is Isaias finally gone?
Mostly. The remnant low of what was once Hurricane Isaias was spinning over the Mid-Atlantic early Monday and was expected to push offshore through the afternoon, according to the NWS Baltimore/Washington forecast discussion. Forecasters let the Flood Watch expire as the heavier rain ended. Showers were likely before 9 a.m. Monday, with another tenth to a quarter-inch of rain possible, before skies turn partly sunny with a high near 74.
If you are still tallying the storm’s impact, see our county-by-county Isaias rain totals and what the rain means for Baltimore’s drought.
How warm will it get, and could Baltimore set a record?
A ridge of high pressure builds over the region through midweek, bringing what the weather service calls “well above” normal temperatures. The forecast for BWI calls for a high near 80 on Tuesday and near 84 on Wednesday. The normal high for mid-October at BWI is about 69 degrees.
According to records from NOAA’s Applied Climate Information System for the Baltimore area’s official record, Wednesday’s record high for Oct. 14 is 86 degrees, set in 1975. Tuesday’s record for Oct. 13 is 89, set in 1954, so a record that day is unlikely. Whether Wednesday gets close depends on how much sun breaks through, so check updated forecasts Tuesday evening.
| Day | Forecast high / low (BWI) | Normal high / low | What to expect |
|---|---|---|---|
| Mon., Oct. 12 | 74 / 57 | 70 / 48 | Morning showers, then partly sunny; gusts to 22 mph |
| Tue., Oct. 13 | 80 / 66 | 69 / 48 | Sunny |
| Wed., Oct. 14 | 84 / 63 | 69 / 47 | Sunny; slight chance of showers at night |
| Thu., Oct. 15 | 70 / 60 | 69 / 47 | Partly sunny, 20%–30% chance of showers |
| Fri., Oct. 16 | 77 / 46 | 68 / 46 | Showers and thunderstorms possible, 40%; turning windy |
| Sat., Oct. 17 | 56 / 38 | 68 / 46 | Mostly sunny, breezy and much cooler |
| Sun., Oct. 18 | 58 / 42 | 68 / 46 | Sunny |
When does the cold front arrive?
A low-pressure system moving from the Plains toward the Great Lakes drags a warm front north on Wednesday night, possibly with a few showers, the weather service said. Its cold front then crosses the region late in the week, raising rain chances Thursday and Friday. The best chance for showers and thunderstorms in Baltimore is Friday and Friday evening, with a 40% chance in the BWI forecast.
Behind the front, highs fall from the 70s on Friday to the mid-50s on Saturday. Saturday night’s forecast low of 38 at BWI would be about 8 degrees below normal.
How windy will it get Friday and Saturday?
A tight pressure gradient behind the front means northwest wind gusts of 20 to 30 knots, roughly 23 to 35 mph, Friday night into Saturday, according to the forecast discussion. Higher elevations to the west could gust to about 40 knots.
On the water, small craft advisory conditions are expected Friday, and near-gale-force winds are possible Friday night. Boaters heading out on the bay this weekend should check the latest marine forecast before leaving the dock.
Could Maryland see snowflakes?
In far Western Maryland, yes, possibly. With gusty northwest winds, upslope snow showers are possible along the Allegheny ridges on Saturday, where highs may stay in the 30s.
“Little to no accumulation is expected although the first flakes of the season are possible.”
National Weather Service Baltimore/Washington, area forecast discussion, Oct. 12
No snow is expected in the Baltimore area.
When does Baltimore usually get its first freeze?
Saturday night’s forecast low of 38 at BWI is above freezing, but colder suburbs and valleys often run several degrees lower than the airport. Based on our review of NOAA daily records for the Baltimore area from 1991 to 2020, the first reading of 32 degrees or lower at the official station came, at the median, around Nov. 1.
What residents can do now:
- Bring tender potted plants inside or cover them Saturday night if you live in a colder, low-lying spot.
- Secure patio furniture, trash cans and decorations before Friday night’s gusty winds.
- Clear fallen leaves from gutters and storm drains ahead of Friday’s showers.
- Plan for a warm Wednesday and a jacket-worthy weekend; temperatures could fall nearly 30 degrees between Wednesday’s high and Saturday’s high.
Forecasts several days out can change, so check for any wind or frost alerts from the weather service before the weekend.
Featured image: The Baltimore skyline from Federal Hill Park. Photo: JJS Photo / Wikimedia Commons, CC BY-SA 2.0.