WEATHER OUTLOOK

The weather pattern this winter and specifically this February, has been unusual to say the least.  Apart from the roller-coaster temperature swings and the over-all mild weather temperatures, the ‘predictability’ of the weather systems this season has been above average.

Indeed, the ‘spread’ of the probability-based ensemble models seems to have been below average in recent weeks indicating higher confidence and lower expected variations in the longer term forecasts.

This is something I haven’t seen much.  Put another way, in past winters, I would check the GFS in the morning and again later in the day and the model forecast had a fairly high chance of having changed in the interim, often dramatically.  Not so in the past few weeks.

For the most part, the remaining two weeks of February look to be similar to recent weeks— Rain, followed by a couple of days of cold weather. then a return to over average temps and more rain as another front moves in.

A cold front moves through tonight (Tuesday) with light rain and cold air and high pressure build in for a two or three day period of cold temps.  Temps moderate by Sunday.

As discussed last week there just haven’t been large/dense cold air masses to sink straight south into the continental US, nor have there been similar masses to set up in the North Atlantic, giving us a ‘blocked’ pattern.

The current pattern looks to continue until near the end of February.  No snow expected.

There have been signs that a pattern change is possibly occurring the very end of February or the first week of March.  The EKDMOS temp stats show very large “spreads” developing in the long range.

EKDMOS High Temp forecasts, showing spread increasing

While there are always larger spreads in the longer range, the latest GFS extended range model forecast is suggesting something is changing.  We’ll see.

 

 

The latest models are still unclear about the amount of cloud cover.  The short range RAP has a break in the clouds during the afternoon—

RAP cloud forecast 12:30 PM

 

The GFS maintains significant clouds in the afternoon—

GFS forecast for 12:30 PM

The GFS did best yesterday.  I guess we’ll see.

There’s not much model agreement with the cloud cover for Sunday. The high resolution models have clouds in the morning with skies clearing during the afternoon.
The GFS has more cloudiness in the afternoon.

There’s also a range of high temps, ranging from 45-50, which reflects the uncertainty in the cloud cover.

Last night, low temperatures approached 10º, (Ft Washington).  This was considerably lower than the 16º predicted by the GFS, NBM and various MOS and LAMP model products.

An average of the CMC (Canadian) and the RAP (Rapid Refresh) model would have been a better forecast.

For today, Saturday, sunny with light winds.  Most of the models have high thin clouds in the afternoon.

Thickening clouds between 2-4 PM, although the latest GFS has pushed that later until 5-6 PM.

An average of the CMC and RAP gives us a high of 30º today (Ft Washington).

Last night’s forecast still on-track for Sunday.

Storm Forecasts & Other Things "up in the air".