2:00pm Monday, March 20:
Yesterday marks the end of a 10-day spell of wintry weather that
featured the largest snowstorm of the season and the winter's longest
spell of below-average temperatures. Total snowfall for the season
doubled during this period, and it sure looks like we'll conclude with
aggregate snowfall of 18.2" (official MU/Lancaster tally). Looking
ahead, I don't see any legitimate threats of snow for the Lancaster
county lowlands...although I won't rule out an onion snow over the
higher terrain in the next couple of weeks.
The large-scale pattern is evolving into a full-fledged Spring
pattern, and I'm confident the temperature trend line is "up" from now
through July! While there will surely be some spells of cooler air
from time to time (after all, there's tremendous snow pack to our
north, especially over NY northward into Ontario and Quebec), I expect
the number of above- and below-average (temperature) days to be nearly
equal through the end of March. This will be exemplified by the week
ahead with highs in the upper 50s Tuesday (above normal), 40s on
Wednesday and Thursday (below normal), and in the 60s on Saturday
(above normal). In the end, March will likely conclude a degree or so
below normal (aggregate "near average") making for the coldest month,
relative to normal, since May 2016.
2:00pm Thursday, March 16:
Tuesday's Nor'easter dropped between 5 inches (south) and 16 inches
(north) across Lancaster county, with 8 to 12 inches most common
throughout the highly populated north-central portion of the county.
Arctic air lingering for several days in its wake will make for the
coldest conditions of the winter, relative to normal, and likely a
couple of new records. Yesterday's high of 26 broke the record for
"lowest max temp" for the day, and tonight's record low of 16 (1916)
is likely to be broken. It's quite remarkable that the final week of
winter will have served up more snow & cold than we saw during the
typically coldest/snowiest month's of the winter (January/February,
A gradual and discontinuous warming trend will being Friday and
continue through next week and into the following weekend. I see three
disturbances that will likely bring us some precipitation during the
next 7 to 10, and perhaps a bit of it will be frozen precipitation.
The good news, however, is that I believe we'll see temps hit the 50s
on at least a couple of occasions next week--next Monday, Friday and
Saturday are candidates for hitting the 50s...and just maybe 60
degrees by next Saturday, March 25th!
In terms of storminess...we first have a clipper to deal with
Friday night into Saturday. A warm front leading this system will
likely bring a few hours of light snow or light wintry mix Friday
night (coating to 1" possible in spots--best chance north of the
Turnpike). By daybreak Saturday, I expect only some spotty drizzle in
the area, and peeks of midday sunshine could lift temps well into the
40s (if no sun, then high temps will hold near 40). The clipper's
upper-level support will reach the coast Saturday PM, and an off-shore
coastal low will form. This system will bring some snow to coastal
NJ, NY, and New England Saturday night...and just maybe wrap a little
snow back into eastern PA sometime Saturday night or Sunday morning.
Otherwise, windy and cold conditions will dominate Sunday with highs
in the low 40s.
Another clipper approaching Monday night will drive a brief shot of
mild air our way on Monday, and so I believe our temps may briefly
hit 50 Monday afternoon. Rain showers Monday night will give way to
windy and cooler conditions for Tuesday and Wednesday, with highs
likely back in the 40s. A strong jet stream trough may then direct a
stronger push of warm air our way by the end of next week...thus the
chance for highs in the 50s to near 60 by the end of next week, along
with rain showers sometime next weekend. The temperature roller
coaster is likely to continue into early April, but thankfully we
won't see air as cold as this week's again until next winter.