EARLY MARCH IN MAY UPDATE

Brief Forecast Update Fri 7:53AM— Some slight changes in the forecast, based on the early morning model runs from (06z or 2AM EDT):

The precipitation moves in earlier today (Friday) with light sprinkles or showers in some locations in the morning and before noontime.

Heavier rain after 1 PM.  The front moves through earlier,  about 8:30 PM instead of 10PM.  Less QPF than previously predicted with totals of about 0.60-0.70 inches water.

With more cold air and faster exit, just a slight chance of the snow flurries about 2 AM.  (Who will see them at that time?)


Updated Added Fri 09:08 AM — Mean low temperatures approach or below 32º from just west of the city and northwest around sunrise.  (standard deviation is 1.5º to 2.2º’;  think of it as ± 1.5 – 2.2º)

Model Blend (NBM) mean low temperatures before daybreak Saturday. (All have standard deviations of 1.5 to 2.0º)      (Click image for a larger view.)

Uncertainty about the amount of cloud cover and instability showers on Saturday: the GFS and NAMNEST have sunshine becoming cloudy mid to late afternoon.   High 48º sd 3.0º Windy to 30+ mph.

The new HIRESW-FV3 (pre-release version has significant periods of clouds and scattered instability sprinkles/(flurries?) throughout the day.

SNOW FLURRIES IN MAY?

With this afternoon’s model runs in, I thought I’d dust off my winter parameter model download scripts.

Here is the latest NAM forecast for 3AM Saturday morning, showing simulated radar and critical snow temperature levels (the white arrows).

It shows our area is cold enough for snow formation (except it will be in mid 30s at ground level).

NAM forecast 3 AM Saturday showing simulated radar and snow critical temperatures all south of our area. (Click image for a larger view.)

I hadn’t seen this for just about all of last winter!

Weather… and Other Things 'Up in the Air'