Brian's exclusive forecast for Baltimore, Annapolis, and northern Delmarva:
Today: Clouds & sun, breezy & cold, few flurries. Highs in upper 20s to lower 30s. NW wind 10 to 15.
Tonight: Clear and cold with a low in the lower to middle 20s. NW wind around 10.
Friday: Mostly sunny and chilly with a high in the upper 30s.
Friday Night: Becoming mostly cloudy with a low in the lower 30s.
Saturday: A brief period of snow and/or sleet, then rain showers. High in the upper 30s.
Saturday Night: Rain showers ending overnight, then cloudy. Low in the mid 30s.
Sunday: Becoming mostly sunny with a high in the low 40s.
The extended forecast calls for windy and colder conditions on Monday with a low in the upper 20s and a high in the mid 30s. Mostly sunny on Tuesday & Wednesday with a low in the mid 20s and a high in the low 40s.
A cold front is progressing eastward this morning, and colder air is overspreading the bay region. Temperatures at daybreak are in the middle to upper 20s, but the mercury will struggle to break above the freezing point today on a fresh northwest wind. Wind chill values will be about five to ten degrees colder than the actual temperature. After a cold night tonight, temperatures moderate a bit on Friday. This weekend, another winter storm will impact the Middle Atlantic states. One low will move northeast from the Tennessee Valley and a secondary low may form off the Delmarva coast. This scenario is known as a "Miller B" storm, which is not the best scenario for central Maryland to get accumulating snow. A "Miller A" storm is the classic coastal low that forms off the Carolina coast and produces heavy snow in our area. With fresh cold air in place over the region, precipitation on Saturday may begin as snow and/or sleet, but will transition to rain as warmer air moves in from the south. Secondary lows are not big snow producers in the Mid-Atlantic and high pressure over New England (a key ingredient to snowstorms in the Chesapeake area) will be moving away rather than holding firm. This scenario supports a mix to rain event for Annapolis. Additionally, when the primary low transfers energy to the secondary low, central Maryland is often in a zone where precipitation is light. Consequently, this Saturday's event will not feature heavy precipitation in the area. As we move into next week, another brief surge of arctic air will overspread the area on Monday but temperatures will moderate quickly into the 40s on Tuesday and Wednesday.
On the Maryland portion of Chesapeake Bay, a Small Craft Advisory is in effect until 6 p.m. Winds today will come out of the northwest at 10 to 15 knots with gusts over 20 knots and waves from 1 to 3 feet. Winds tonight will come out of the west at 10 knots with waves around one foot. Winds on Friday will come out of the southwest at 5 to 10 knots with waves around one foot. Winds on Friday night will come out of the southeast at 5 to 10 knots with waves around one foot. Marine information is provided only as guidance. Boaters should always stay tuned to the latest forecasts and advisories from the National Weather Service.
The average high temperature for December 12 is 46 degrees and the average low is 29 degrees. The records at Baltimore on this date are 71 degrees in 1979 and 10 degrees in 1988. Today's sunrise will occur at 7:17 and the sunset will occur at 4:43. Weather data courtesy of the National Weather Service. For more weather updates, please visit my Chesapeake Bay Weather page on Facebook, and if you're heading to Ocean City feel free to check out my Ocean City MD Weather page on Facebook. You can also follow me on Twitter @chesbayweather.