Baltimore is set for a brief stint of high pressure this weekend, but don't get too comfy. A strong cold front is on its way Sunday evening, and it's bringing Canadian high pressure right behind it, which can only mean one thing: brace yourself for a chilly start next week. According to the National Weather Service Baltimore MD/Washington DC, before the cold front hits, we've got a series of frontal systems queued up over the Upper Midwest, and a weak high-pressure sandwich in our own backyard. But before you rejoice in the calm winds, heed the warning: icy drizzle has prompted Winter Weather Advisories, which have been extended until 7 AM today in some areas.
Temperatures won't budge much from the upper 20s to low 30s this morning while we're stuck under a blanket of low stratus; the sun's not quite strong enough this time of year to chase away the clouds before noon. But there's a glimmer of good news, the afternoons may bless us with some late-day sunshine, even if it means highs still hovering only in the low to mid-40s, and the mountains, well, they'll be chillier, think upper 20s to 30s, and even though much of the region should stay dry a few stray upslope showers in the Alleghenies could mix things up a wintry notch but with so little moisture in play the disruption should be nothing to write home about.
As we peek ahead to Sunday and Monday, the word on the streets, or should we say skies, is an Arctic boundary steaming over from the Rockies, ready to mix it up with tranquil weather through Sunday as weak high pressure keeps things steady, but just a few shades cooler than what we're used to this time of year, preparing us for the main event: the blustery cold front Sunday night. Any precipitation chances are locked over the Alleghenies, which is to be expected given a very low Froude number (<0.50), the National Weather Service stated, meaning hold on to your hats (and coats) for a brisk and briskly cold start to your workweek. Monday night, the anticyclone moves overhead, resulting in a very cold night indeed and lows likely to plunge into the teens, though some urban centers might cling to the low 20s.
Tuesday to Friday, we're caught in the icy grip of an eastern Canadian trough, throwing shortwaves that jostle the weather pattern, leading to several "maybes" when it comes to precipitation — Wednesday might warm enough for rain except for the mountains, yet the tail end of the week could go either way with a complex dance of jet streams causing forecasters some headaches, as they put it, "It is important to note that this period could also remain entirely dry as well," says the National Weather Service, so we'll just have to wait and see as the pieces fall into place.
For the aviators out there, the snowpack, light winds, and saturated layers are generating widespread IFR to LIFR restrictions, with VFR conditions not expected to return until the afternoon as things finally clear up on Saturday. Sunday through Wednesday calls for some wind shifts: post-frontal northwesterlies replace the milder vibes of Sunday, turning northerly on Monday, and come Tuesday, expect southbound gusts up to around 20 mph.
On the waters, mariners will catch a break with light winds thanks to weak high pressure. Under 10 knots all weekend long — but don't let your guard down, a stronger front Sunday night ushers in gustier conditions, potentially triggering Small Craft Advisories well into Monday, with the NWS not ruling out a few gales for the more southern waters.
