After Saturday AM, Warm End to 2025

After a cloudy Wednesday, a showery Thursday, and a chilly Friday, it’s nothing but warm and mostly sunny weather to close out the year. How warm? How about 10 out of 11 days reaching over 70 degrees. Two or three days could reach the upper 70s! The only concern for Christmas week will be morning fog. The culprit: A big upper air ridge keeping the jet stream, storms, and cold air close to the Canadian border — far away from us.

Read the next section for specific details, or finish this section out for my brief, geeky weather lesson.

The National Weather Service forecast maps shows us in showers (green colors) for Thursday morning. However, there’s no fronts nearby, so why the rain? (The red hatched area means a chance of thundershowers).

Answer: Look at the upper air forecast for the same time where a trough or wave in the southern jet just to our west (the broad yellow “U” over the Western Gulf) that will pass through us Thursday AM. That means we’re in an area of upward motion where air rises, cools, and condenses giving clouds and often rain. Note that there’s another wave in the northerly jet over Oklahoma (the green “V”), which will be sweeping through to our north later in the day giving inland areas a chance of showers. It will also drag a cold front down giving us Friday’s chill. So now you know why meteorologists dream in colored contours.

The Foreca graphic overdoes the rainfall tomorrow (X-ed out), but otherwise captures the details well. Tomorrow will be a mostly cloudy day courtesy of warm air riding up over cold, dry air gradually moistening it. Yes, we could see a few afternoon sprinkles, but they won’t amount to much. The main action happens after midnight in the wee hours of Thursday morning when showers move in. Yes, you could hear a clap or two of thunder near the coast. Showers could linger through the morning hours, then clouds will thin out and we could see some sunshine in the afternoon in most areas. However, another batch of light showers will move in the late afternoon or evening hours in inland areas. Overall, expecting a few tenths of an inch.

Then, cold air filters in for Friday and Saturday morning. Friday’s highs reach the low 60s. This time, temps won’t reach freezing, with 39-40 degree readings in most suburban and rural areas of the Northshore for Saturday morning. Expect 45-50 degree lows south. Then, a quick warm up to the low 70s will have you shedding jackets and sweaters by late morning. After that the warmth is on. Watch out for fog in the morning next week.

Not much to say here except: 1) Christmas day should dawn foggy, then clear. Lows upper 50s. Highs low 70s. 2) After Christmas, highs could reach mid-upper 70s for a four-day stretch, again with sunny weather. 3) A weak front seems possible about Dec. 28th or 29th, which could lower temperatures to highs 60s. Lows near 50. Winter is not done, expect the early December pattern or warmth in the West, and cold in the East to return after the first few days of January.