Cooldown tomorrow, warm weekend
After a powerful storm moved through the region yesterday, cool, but not cold air moved in behind it, as temperatures dropped back into the 40s for highs today. The weather looks to generally be pleasant, but some leftover shortwave energy behind the storm will trigger enough lift to keep skies mostly cloudy for most of the day.
This shortwave energy has triggered a weak cold front, which will move through the area tonight. This is when a brief return to “winter” will truly be felt, as temperatures will drop back into the 20s tonight. Lift in the atmosphere will have a lid, thus clouds should clear.
Tomorrow will feature northwesterly and northerly flow from Canada, which will allow temperatures to only hold in the mid to upper 30s. While that doesn’t seem super cold, the average highs this time of year are in the low 40s. We will have a moderate breeze out of the northwest.
Tomorrow night looks quite chilly, as the due northerly flow takes over, which is the most efficient way to draw in cold air at the surface. Low temperatures look to be in the upper teens.
Today’s NAM Model valid for Friday morning shows temperatures falling into the teens for most of the area.
On Friday and the weekend, this mini-trough will be moving out and allow for a more zonal flow to develop. This zonal flow has Pacific origins, and not Arctic, which will allow temperatures to warm up as the weekend goes on. Friday should warm up into the low 40s, but then a shortwave will develop on the leading edge of the warmer air will move in on Friday evening and could give us a few rain and snow showers — nothing significant. Once Saturday and Sunday come around, temperatures in the low to mid 50s become likely! With the stronger sun angle this time of year, it might feel quite warm in the sun — Saturday might not be bad for some outdoor activities provided we get a mostly sunny sky. However, some onshore flow may make it difficult for the coast to also get into the 50s.
After a few showers on Sunday night/early Monday morning, there looms a storm threat sometime in the next Tuesday through Thursday period. There is still a lot of uncertainty with this one — it could either be rain, snow, a mix of both, or out to sea. Right now, we are generally leaning in the “warmer” direction, which could mean some snow but mostly rain — but it is still very early and only a few small tweaks could turn this into a major snowstorm for our area.