Tidal Potomac from Key Bridge to Indian Head MD Marine Forecast
| Rest Of The Overnight...Sw Winds 5 Kt. Waves Less Than 1 Ft. A Slight Chance Of Showers. |
| Today...W Winds 5 To 10 Kt. Waves 1 Ft. Showers Likely With A Chance Of Tstms. |
| Tonight...N Winds 5 To 10 Kt. Waves 1 Ft. A Chance Of Showers And Tstms. |
| Thu...N Winds 5 To 10 Kt. Waves 1 Ft. |
| Thu Night...Ne Winds Around 5 Kt. Waves 1 Ft Or Less. |
| Fri...E Winds Around 5 Kt. Waves 1 Ft. |
| Fri Night...E Winds Around 5 Kt. Waves 1 Ft Or Less. |
| Sat...Se Winds Around 5 Kt. Waves 1 Ft. |
| Sun...S Winds Around 5 Kt. Waves 1 Ft. A Chance Of Showers Through The Night. Winds And Waves Higher And Visibilities Lower In And Near Tstms. |
| Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 357am EDT Wednesday July 22 2026 .WHAT HAS CHANGED... Confidence is slowly increasing on where the highest shower and thunderstorm chances will be this afternoon and evening. Small Craft Advisory were issued for tonight into Thursday morning. Timing of the next chance of rain remains uncertain for this weekend into early next week. .KEY MESSAGES... - 1) A few strong to severe thunderstorms are possible from central Virginia to southern Maryland this afternoon. - 2) Below average temperatures and mainly dry conditions are expected Thursday through Saturday. KEY MESSAGE 1...A few strong to severe thunderstorms are possible from central Virginia to southern Maryland this afternoon. The cold front appears to be just southeast of Lake Erie as of 3 AM with the upper level trough axis across the eastern Great Lakes down into the Ohio Valley. The heaviest rain has exited the area. Convection that has been developing west of the Appalachians has been dissipating as it crosses the ridge into more stability and encounters downsloping flow. A few areas of light showers/sprinkles still exist though. With clearing skies and relatively light winds, a few patches of fog could form, but it is unlikely to be widespread. A prefrontal trough will switch winds to westerly through much of the day before northerly winds bring the true airmass change tonight. The cold front likely overtakes the trough at some point but will temporarily stall this afternoon, likely extending across central Virginia to southern Maryland. Dew points will remain in the 70s in this area, supporting some instability to go along with the wind shear provided by the upper trough. Scattered to numerous showers and thunderstorms are forecast along and southeast of the front, although there remains some uncertainty in coverage and intensity. Given the shear in place, there is some potential for severe thunderstorms, with damaging winds being the primary threat. Thunderstorms may also be repetitive along the slow moving front, but the expected fast individual storm motions will likely preclude any flood threat. The front will drop south of the area this evening, but an area of low pressure may ride along it. This could result in additional showers spreading across central Virginia and southern Maryland through the night. In terms of temperatures, highs today will be in the 70s to lower 80s west of I-81 and mid to upper 80s to the east. Lows tonight will drop into the 50s and 60s, and some of the sheltered high elevation valleys could reach the 40s. KEY MESSAGE 2...Below average temperatures and mainly dry conditions are expected Thursday through Saturday. A sprawling area of high pressure will build to our north for Thursday and Friday, before shifting off the New England Coastline on Saturday. Northerly flow ahead of the approaching high will advect a much cooler and drier airmass into the region for Thursday. Well below normal temperatures and dewpoints are forecast for late July, with high temperatures only in the upper 70s/low 80s. Dewpoints in the 50s will also make it feel much less humid than is typical for July. Mostly sunny skies will accompany the well below normal temperatures/dewpoints. Temperatures will stay well below normal for Friday and Saturday within easterly flow. Some moisture could be drawn northward from the stalled frontal zone across the southeastern states during this time. The current forecast has some low rain chances both days, mainly in southern portions of the CWA (County Warning Area) and along the Allegheny Mountains. Both temperatures and dewpoints begin to rise again on Sunday as flow turns southerly, with highs in the mid to upper 80s and dewpoints in the 60s. The return of higher dewpoint air should lead to slightly greater chances for afternoon/evening showers and thunderstorms, but most locations will likely still stay dry. Forecast confidence decreases substantially by Monday and Tuesday, but chances for showers and thunderstorms may further increase as multiple shortwave disturbances move through in northwesterly flow aloft. Depending on how the forecast details evolve, there could be a conditional threat for severe thunderstorms on either Monday or Tuesday. Marine It appears earlier storms have stabilized the atmosphere, so portions of the existing Small Craft Advisory may be cancelled early. Some continuation of advisory conditions is expected into the day on the wider mid-bay waters. Additional strong to perhaps severe thunderstorms may develop ahead of a cold front this afternoon and evening across mainly southern Maryland. A pressure surge and accompanying shift to northerly winds will push across the waters this evening. Small Craft Advisories have been issued for tonight into Thursday morning along the bay. Thereafter, sub-SCA (Small Craft Advisory) level winds are expected Thursday afternoon through Sunday. Winds will generally be out of the north on Thursday, east on Friday, and southeast on Saturday and Sunday. Tides / Coastal Flooding Anomalies remain between 0.5-1 foot this morning. Havre de Grace may approach minor flood stage this morning but should remain below. Water levels will drop as a cold front passes later today. NOAA Baltimore MD/Washington DC Office: Watches - Warnings - Advisories DC...None. MD...Small Craft Advisory until 8am EDT this morning for MDZ008. Small Craft Advisory from 9pm this evening to 8am EDT Thursday for MDZ008. VA...None. WV...None. Marine Small Craft Advisory until 8am EDT this morning for ANZ530- 531-539. Small Craft Advisory from 9pm this evening to 8am EDT Thursday for ANZ530>532-539-540. Small Craft Advisory until noon EDT today for ANZ532-533- 540>542. Small Craft Advisory from midnight tonight to 11am EDT Thursday for ANZ533-534-537-541-543. Small Craft Advisory until 6pm EDT this evening for ANZ534- 537-543. Small Craft Advisory until 4am EDT early this morning for ANZ536. |
Baltimore/Washington Radar
Northeast Radar
East Coast Satellite