The top story in New England's weather this week will continue to be the short but severe arctic blast coming on Thursday night and continuing through Sunday morning. Northern New England will get a taste of the fierce air coming tonight. Temperatures will slowly fall, as usual, throughout the evening tonight. However, once the clouds from our most recent disturbance clears and the winds die down, the temperatures are going to bottom out.
Low temperatures tonight will be as low as -15° across the higher elevations of the north with wind chills dipping into the -20s to near -30 in some spots. Areas of New England south of Lake Winnipesaukee will not see as dramatic of temperatures tonight. Low temperatures from Manchester and Portland southward to Hartford will fall to the teens and 20s. There is some uncertain in the lows tonight across southern New England. The NWS of Boston states:
"...some uncertainty to lows and potential for busting too high; thinking stronger radiational cooling then either slows or is halted as midlevel clouds increase towards overcast."
Despite the uncertainty, lows will not fall below zero across southern New England tonight. Tonight remains just a small taste of the epic arctic blast coming later this week. This blast of air is expected to penetrate the region Thursday night through the day on Friday. Highs on Friday will occur in the morning and temperatures will plummet throughout the day across the region. Here's the timing of this blast of air:
FRIDAY
In northern areas, Friday's morning high will already be bone chilling. Stowe, Vermont's morning high will be a mere 2°. By the afternoon, the temperature will have fallen to near -10°. The sharp drop in temperatures will be felt region wide. Boston will see a morning high of 30° with temperatures falling to the single digits by the afternoon.
FRIDAY NIGHT
Temperatures will continue their plummet throughout the night. Lows will likely bottom out in the -10s in much of Massachusetts, except for the coast. Northern New England will see temperatures drop into the -10s to -20s. These are air temperatures. Winds will be very gusty during this time, with 20 to 30mph winds likely throughout the region. This will create wind chills in excess of -20 to -30 in much of the region.
SATURDAY
By early Saturday morning, New England will be firmly in the grips of the arctic air mass. Morning lows will range from the negative single digits south to the -20s north. Wind chills will be in the -20s in southern New England. Higher elevations of the Berkshires as well as exposed coastal areas may drop to the -30s. In northern New England, the wind chills will truly be dangerous, with lows hitting the -30s to -40s. In higher elevations, chills will likely hit the -50s.
Afternoon highs will not rebound too much. Highs on Saturday will range from the teens south and the single digits, on either side of zero, north. Wind chills will remain well below zero all day across the region.
SATURDAY NIGHT
Temperatures overnight Saturday will be similar to lows seen on Friday night. In some areas, the temperature may even get a notch colder than the previous night. The high pressure system will depart on Saturday, but radiational cooling will remain strong and the high pressure's influence will remain in place despite its departure. Winds will begin to back off. While the winds will never reach strong status, any wind in the air with temperatures this cold will cause a massive difference in the feels like temperatures.
SUNDAY
Despite the day starting off similar to Saturday morning temperature wise, the afternoon will be far different. The temperatures will rise almost as quickly as they fell on Friday. Sunday afternoon highs will be in the 30s for most of the region. In southern New England, highs could even reach the low 40s. This translates to the temperature rising 30 to 40 degrees during the day.
As intense as this arctic blast will be, not all the ingredients are together for it to reach its full potential. The NWS of Gray, Maine states:
"In the end wind chills will be the main story Fri night...as the air temps will be cold but unlikely to break many records. The mixed environment Fri night will likely prevent temps from realizing their full potential given the air mass. Lows should fall into the 20s below zero in the north...and teens to single digits below zero elsewhere...but wind chills may potentially fall into the 30s...40s...and 50s below zero by Sat morning."