MD Weather Alerts
Evening / Overnight Edition · Sunday, September 13, 2026
Good evening. The muggy, showery weekend pattern is finally packing its bags. A secondary cold front slides through Maryland tonight, wringing out a few lingering showers — mainly across the western high country and I-95 corridor — before clearing skies and a noticeably cooler, drier air mass take over for the start of the workweek. Both NWS Baltimore/Washington (2:22 PM update) and NWS Mount Holly (4:54 PM update) agree: any leftover rain fizzles out by midnight to a few hours after, and Monday wakes up feeling like fall arrived early.
Tonight’s Timeline
- 6–9 PM: Scattered showers continue to wane across central Maryland and the Eastern Shore as the departing coastal low pulls away. Nothing widespread, mostly hit-or-miss.
- 9 PM–Midnight: The secondary cold front pushes south into the Allegheny Front and western Maryland, capable of a brief shower or isolated rumble of thunder, especially Garrett and Allegany counties. Ocean City may also see a passing shower/storm as the front’s tail end brushes the coast.
- Midnight–3 AM: Showers should be diminishing area-wide as the front clears the state. Skies begin clearing behind it.
- After 3 AM: Dry, clearing, and turning noticeably cooler and less humid area-wide ahead of Monday’s breezy, refreshing start to the week.
Region by Region (Tonight into Monday)
Western Maryland
Garrett County (Deep Creek/Oakland): Lows tonight near 56°, with isolated showers giving way to patchy valley fog after midnight — watch for reduced visibility on Rt. 219 early Monday. Monday itself turns mostly sunny and cooler, high around 66°, breezy out of the northwest. Allegany County (Cumberland): Low around 61° with a 20% chance of a lingering shower before skies clear. Monday: patchy morning fog, then sunny and pleasant, high near 74°.
Northern & Central Maryland
Washington County (Hagerstown): Partly cloudy tonight, low near 64°, only a slim 7% shower chance. Monday sunny and breezy, high near 77°, north winds gusting 15-20 mph. Frederick County: Isolated showers early tonight (9% chance) fading to partly cloudy skies, low around 67°. Monday sunny with gusty north winds, high near 79°. Carroll County: Same story — low around 67°, a stray shower possible before midnight, then clearing. Monday sunny and breezy, high near 79°.
Baltimore Metro
Baltimore City & County: Isolated showers possible early tonight (16% chance) then partly cloudy, low near 70°. Monday full sun, high near 79°, with north winds gusting near 20-25 mph — hang onto the patio umbrellas. Harford County: Similar setup, low near 70°, breezy and sunny Monday, high near 79°. Howard County: Low around 70°, a passing shower possible before clearing, Monday sunny and crisp near 79°. Anne Arundel County: Low near 69-70°, isolated shower chance early, clearing overnight; Monday sunny, breezy off the water, high near 79°.
DC Suburbs
Montgomery County: Scattered showers possible early evening (up to 25% chance) tapering to isolated activity overnight, low near 69°. Monday sunny and breezy, high near 79°, gusty north winds around 13 mph. Prince George’s County: Same trend — low near 69°, lingering isolated shower chance, then clearing. Monday sunny, high near 79°.
Southern Maryland
Charles County: Isolated showers possible tonight (15% chance), low near 69°, clearing toward dawn. Monday sunny and breezy, high near 81°. Calvert County: Low around 69°, similar isolated shower risk fading overnight. Monday sunny, high near 81°, brisk northerly winds. St. Mary’s County: Low near 69-70°, isolated shower chance early before clearing. Monday sunny, high near 81°. Tide levels stay elevated tonight — Annapolis and Havre de Grace could brush minor flood stage on high tide, so low-lying docks and roads near the water deserve a glance before bed.
Upper Eastern Shore
Cecil County: Partly cloudy tonight, low near 71°, minimal shower chance. Monday sunny and breezy, high near 81°. Kent, Queen Anne’s, Talbot & Caroline Counties: Low around 71°, just a 4% shower chance — essentially a dry, partly cloudy night. Monday sunny with gusty north winds up to 15 mph, high near 81°.
Lower Eastern Shore
Dorchester, Wicomico & Somerset Counties: Mostly clear tonight, low near 70°, only a 13% shower chance early on. Monday turns sunny and breezy, high near 81°, with a refreshing drop in humidity.
Ocean City & the Coast
Worcester County: The coast holds onto the best shower/storm chance tonight at 25%, as the front’s tail end and any leftover instability move through before midnight, then skies turn partly cloudy. Low near 71°. Monday brings a big turnaround: mostly sunny, high near 78°, with brisk north winds gusting into the teens-to-near-20 mph range. Beaches: Surf running 2 to 3 feet, rip current risk low for Monday but climbing to moderate by Tuesday — swimmers should still respect the flags and check with lifeguards. High tide at the Ocean City Fishing Pier Monday at 10:18 AM, low at 4:41 PM. Water temps holding in the upper 70s, UV index high, so sunscreen still matters even with the cooler air.
Active Hazards
No watches, warnings, or advisories are in effect for Maryland’s land areas at this time.
On the water, however: a Small Craft Advisory is in effect from 4 AM to 10 PM EDT Monday for the Chesapeake Bay north of Pooles Island, the Bay from Pooles Island to Sandy Point, Sandy Point to North Beach, North Beach to Drum Point, Drum Point to Smith Point, the tidal Potomac (Key Bridge to Indian Head, Indian Head to Cobb Island, Cobb Island to Smith Point), and Baltimore Harbor/Patapsco River. A separate Small Craft Advisory runs from 4 AM Monday through 7 AM EDT Tuesday for the Chester River to Queenstown, Eastern Bay, Choptank/Little Choptank rivers, and the Patuxent River to Broomes Island. Boaters on the Bay and tidal rivers should expect gusty northwesterly winds up to 20-25 knots behind the front — small craft should stay in port Monday.
Severe Weather & Flooding
Severe potential tonight is low. Any showers or an isolated rumble of thunder along the front, mainly over the western mountains before midnight, should be weak and brief — forcing and instability are both modest, and increasing subsidence aloft is capping things further. No flooding concerns are expected from rainfall. The only water-related item is the minor tidal flooding risk mentioned above for Annapolis, Alexandria, and Havre de Grace with tonight’s high tide.
Heat, Humidity & Winds
Muggy air lingers into this evening but breaks down decisively behind the front. By Monday, dew points crash into the upper 40s to mid-50s — a sharp, welcome change after a sticky weekend. Winds are the headline for Monday: a tight pressure gradient with a strengthening 1024-mb high approaching from the Great Lakes drives a breezy northwest wind area-wide, with gusts of 20 to 25 mph possible, strongest across the Baltimore/DC corridor and the Bay shorelines. Secure anything loose on porches and decks.
Overnight Lows by Zone
| Zone | Low Tonight |
| Western Mountains (Garrett) | Around 56° |
| Cumberland/Hagerstown | Low-to-mid 60s (61–64°) |
| Frederick/Carroll | Around 67° |
| Baltimore/DC Corridor | Upper 60s (69–70°) |
| Southern Maryland | Around 69° |
| Eastern Shore | Upper 60s to low 70s (70–71°) |
| Ocean City | Around 71° |
Looking Ahead
Monday is the pick of the week — sunny, breezy, and refreshingly dry, with highs in the mid-70s to low 80s (5 to 15 degrees cooler in the mountains). Monday night turns crisp under a strong dome of high pressure, with lows plunging into the upper 40s to 50s statewide — grab a light jacket if you’re out late. Tuesday keeps the autumnal feel with plenty of sunshine and lighter winds before a warm-up returns by midweek, with highs climbing back toward the mid-to-upper 80s by Wednesday and Thursday. Later in the week, a cold front approaches with increasing humidity and a chance of showers and thunderstorms Thursday into the weekend — severe potential currently looks minimal, but we’ll keep watching timing as it firms up.
Data: NWS Baltimore/Washington, Mount Holly & Wakefield.
MD Weather Alerts — your director’s cut of the Maryland forecast, county by county, front porch to shoreline. Stay dry, stay cool, and enjoy the break from the mugginess.