THURSDAY AFTERNOON

Unbelievable!!!  After a badly busted forecast of this morning’s lows, local weather authorities are poised to do it again tomorrow.  My guess is that they haven’t learned anything from this morning’s fiasco.  Anyway, they’re shooting for -11 tomorrow morning while four of their major forecast tools predict 3, zero, -2 and 5.  On average, slightly warmer than their forecasts for today.  This morning, the busted forecast was due to the winds.  Tonight it’ll be due to increasing clouds  after midnight.

NOTE:  Missing a temperature forecast by 9 degrees or more has become a real rarity these days.  I’d guess it happens less than 10 times a year here.  Coming with all the Watches and Warnings in place (dependent on the forecast), it was a real embarrassment for us forecasters.

Friday-Saturday storm

We’re getting close enough to the arrival of the next storm to be able to try to make some sense out of it (although a few doubts remain).

In general, the models are thinking along the same lines although the NAM is faster (and cooler) than the GFS models.  The upper trend is for another polar jet disturbance to sink southward over the western Plaines and Rockies.  Unlike the past several storms. this trough will hold back in the western U.S. and send us ripples of energy over the weekend.  But, the main part of the system does not play a major role in the weekend’s activities.

Meanwhile, the subtropical jet is available to send plenty of  moisture our way.  Here’s how it’s shaping up:  Increasing clouds begin tonight with a cloudy cold day Friday.  We could see some very light snow or flurries during the afternoon.  High near 24 degrees.  Temperatures continue rising tomorrow night as snow becomes heavier.  In fact, 2″-4″ of snow appears likely before a changeover to sleet and freezing rain Saturday morning.  By Saturday afternoon temperatures will rise above freezing so freezing rain will change to rain and begin a long cleanup.

Doubts:  models have backed off a bit on the 1″-2″ rain totals, so the prospect for flooding will be much lower.  HOWEVER , many urban streets/intersections will flood because the storm sewers will be blocked by snow.

Biggest question mark remaining is the duration of the sleet and freezing periods.  At this time, it looks like the freezing rain will be the biggest threat – a lot of ice is possible, especially if the NAM is better than the GFS.  More tomorrow.