Disc: For info on the very near term, i.e. today's amounts and specific points in the very near term, refer to our Facebook page. This outlook will focus more on later tonight, tomorrow, and beyond.
Currently: Double barrel low pressure extends from SE AL to near Myrtle Beach. High pressure, which is keeping the cold air in place at the sfc, stretches from Nrn New Eng, to Central Canada.
Tonight: Steady pcpn will diminish. However, periods of snow and sleet, with minor accums, are possible all night. In addition, in areas where pcpn does not fall, some light freezing drizzle could fall. This will keep roads and sidewalks very slippery overnight, so exercise extra caution. As for temps, I went close to guidance. Temps should be steady or slowly rise thru the night, and by morning, be in the mid to upper 20s- still plenty cold enough!
Tomorrow: Models are in reasonable agreement, however, models have not done a very good job overall this winter, so confidence is still a bit lower than it should be. The general idea is for a coastal low to develop and spin more, mostly light, precip over the area. The general evolution, at least the best I can come up with, is something like this: steadier precip will redevelop in the morning. It may not develop as snow right away, since the thermal profiles aloft do not support 100% snow. However, it will transition to all snow as the upper levels cool. Snow may then even come down moderate at times. In fact, it may snow until midnight tomorrow night! At least minor additional accumulations are expected, with some potential for more than that! I went 3-5 deg below temp guidance tomorrow, as precip falls thru a cold column and cools the atmosphere. Temps should still rise a few degrees, and make it to near 30 or so for highs.
For tomorrow night into Saturday, snow ends by midnight tomorrow night and skies clear. Sat should be sunny and cold. There is the potential for snow squalls/showers with the secondary front Sat aftn, w/the greatest chance, as usual, over the NW Hills. W/fresh snow pack, and the potential for more clouds than modeled during the heat of the day, I went a couple deg below guidance. Look for highs right around the freezing mark. There will also be a breeze, adding to the chill.
Long Term (Sun and beyond): There are two focal points in the long term. The first is Monday and the second is just outside our forecast period, but I may throw in a little teaser.
First, for Sunday, a sunny, cold winter's day. I'll undercut guidance a couple deg again w/deep snowpack. Look for highs once again around the freezing mark.
For Monday, a storm system is slated to affect the area. This is a Miller B system- an Alberta Clipper that transfers to a coastal. Lots of questions still remain, such as when the transfer occurs and when we can really get the sfc low going. The GFS and ECMWF have trended colder at the sfc and have trended stronger w/sfc low development. However, they tend to develop the low too late for all of CT, which is possible. The GGEM does not have much coastal development, but has a colder sfc to begin with. A snow shower is possible everywhere Mon morn. Then a lot depends on the development of the coastal low. An earlier, faster development would get the entire state in the game for snow, possibly significant, or at least moderate. Otherwise, it will be a battle between the sfc and upper air, w/upper air temps supporting snow or sleet, and the sfc possibly too warm, esp in S CT. That would yield a situation where heavier precip would bring down snow or sleet and lighter precip would be rain. For now, based on the modeling and evolution of this sys, NE CT is favored for the higher chc of higher accums. As for temps, a lot depends on the evolution of the sys as a whole, but chopping 5 deg off the NBM temps seems like a good start for now, since even the models w/no coastal have decent rates of precip falling. This yields highs in the mid 30s.
The rest of the week is fairly quiet. Tuesday should be fair, with moderating temperatures. Since there is still snow on the ground regardless of what happens Monday, I subtracted a couple deg off guidance. This gives us highs generally in the upper 30s, but a few low 40s in the I 91 corridor.
For Wed, I went close to guidance temps. Despite snowcover, there is strong warm air advection ahead of the next cold front. These should probably cancel each other out. Mid to upper 40s may feel like spring!
A weak clipper system and associated cold front affect the state on Thursday. I went way below temp guidance here, as there are showers falling and very cold air aloft. So look for highs around 40. As for precipitation type, I am calling for all snow with these showers, but no accum is expected due to warm sfc temps.
Now just beyond our fcst period, a poleward-moving low looks to come up the coast again. It appears there is good sfc high pressure to the north. Models are very divergent on track, ranging from the GGEM taking it up into the lakes and the GFS taking it out to sea, basically expected at this range, stay tuned!
No time for graphics today, refer to our Facebook page for snow maps!
See you next week!
-GP!
