Joe’s Weather Blog: Underestimated cold potential + Saturday mischief?

15403859_10153980024431681_5436975346317281205_o

Good afternoon: Every so often I underestimate the air mass coming into the area…and I think I did that with this air mass today. We saw a cold front move into the area yesterday afternoon…I should’ve lowered my temperature more for the lows and highs today I think in retrospect. We bottomed out at 14° this morning and as of noon we’re still in the 20s. My forecast high today was 41° and I have a feeling I overshot the potential and underestimated the colder air strength that moved into the area. Let’s see how fast we can warm up this afternoon but I have my doubts.

Forecast:

Tonight: Variable clouds and chilly with lows in the teens

Tuesday: Partly cloudy with highs 25-30°

Wednesday: Mainly cloudy and chilly with highs 25-30°

Discussion:

So I’ve been starting the blogs lately with a Christmas musical selection that you can play and listen to while you read my weather thoughts…today’s selection is from the incomparable Tony Bennett.

 

I’ll blame my 3+ week cold/flu whatever that I’m trying to get rid off for the failure to see the cold potential for today. My 1st clue should’ve been the NW winds of 20-30 mph yesterday evening…my 2nd clue should’ve been the colder temperatures that were present in NE moving this way. I’m somewhat mad at myself about that.

It’s an important admission because we’re going to be seeing more of these types of air masses with perhaps the coldest one coming this weekend. So I need to watch this more carefully…when these fronts come through. I would’ve been more aggressive IF I saw more snow cover towards the NW of here…there is some north of I-80 but I’d like to see more south of there personally as well as a stronger area of high pressure building southwards…but in reality the high pressure area (from a pressure standpoint) isn’t particularly strong in the scheme of things.

Today…the colder air is is trying to move away. Surface winds are from the SW now…but not very strong. So w’re not “mixing” the lower part of the atmosphere well…plus now we’re seeing some high clouds filtering out the sunshine. That is NOT a good combination to forecast highs into the 40° range.

 

The map above is the surface map showing the wind direction and also isobars (contoured) which are lines of equal pressure. When the lines are spaced apart..as you get closer to the center of the high in central MO this afternoon…the winds are lighter…when the isobars are packed together…the winds are stronger at the surface. We’ll see plenty of that type of weather later this week into Saturday (remember this information)

Now the satellite picture…showing increasing high clouds along and south of the I-70 corridor…also note the “veinous” nature of the white colors (this afternoon if you’re reading this) towards and north of I-80 A lot of that white is actually snow on the ground.

1kmv

Notice the rivers showing up in the snow field across northern NE and the northern half of IA

There is actually some broad scale lifting going on in a relatively dry atmosphere across KS spreading eastwards. I don’t think there is enough moisture out there to stir up any snow this evening…but I guess a random flake isn’t out of the question towards the east of KC.

With that said…now take a look at the next air mass moving southwards through the northern Plains. The leading edge is another cold front that will move through the area overnight. At 11AM the front was up towards NE…notice the near 0° temperatures in the northern Plains…granted there is a good cover of snow on the ground up there making that air mass colder.

sfc

Sometimes when these air masses move through it’s actually easier to see them by going a few thousand feet above the surface…and watch the movement of the temperatures…let’s do that using the NAM model. The increments are every 3 hours and it goes out to 84 hours (via NEXLAB)

925

Approx 3000′ temperatures …notice the colder air sweeping in…then there are repeated reinforcing pushes into Thursday

So that is why it’s going to be cold for a few days…The other issue will be cloud cover…any decent cloud deck…and I think there is going to be a lot of that…will easily knock down the temperatures during the day. Also of note…those same clouds overnight keep the temperatures up…I think this is what we’re looking at for a few days. There is bust potential in the nightly lows especially…because IF we lose the clouds…it can easily get MUCH colder than what a forecast may or may not show. Just like removing a blanket on a cold night makes you cold fast…same effect with removing the clouds. The opposite is try as well…forecasting really low readings…then can easily bust too low because of unexpected clouds coming into the area. So that will be taken on a day be day basis.

Now about the late week potential…

A surface storm is going to get it’s act together across SE CO later THU into FRI. This will allow warmer air to return northwards with some gulf moisture. So after a cold TUE>THU…we should moderate somewhat FRI into FRI night (perhaps even with warming temperatures FRI night).

Here is the GFS forecast map for Friday morning…

gfs108hr_sfc_mslp

Note that big surface high in MT…that is going to have the mother lode of cold air that will move in 1st thing Saturday and linger into next Monday

 

Ahead of the low some moisture will stream northwards…and you can see that with the surface dew points.

gfs108hr_sfc_dewp

GFS modeled dew points

An issue is though that while some moisture will come up…there really isn’t anything to get that moisture into the form of anything aside from drizzle or perhaps a few passing showers Friday (also need to watch the temperatures at the onset of anything forming). The main energy is still out towards CA Friday…

Then the cold (frigid) air mass moves into the area Saturday…then it gets more interesting. Temperatures will drop again below freezing…perhaps substantially so as the day moves along. Will this piece of energy out there come over the cold air mass at the right time? This is somewhat similar to what the set-up was last week..and that didn’t work out so great for snow lovers. The GFS and it’s ensembles says someone in the viewing area has the potential of seeing 2-6″ of snow. The EURO is showing somewhat of the same type thing…this would be concurrent with temperatures plunging into the teens during the day with very gusty winds sending wind chills below 0° I think. As a matter of fact the EURO model shows temperatures near 10° by 6PM that evening with some snow (***note to the NW MO State Bearcat fans***) and the potential for sub-zero lows Sunday morning (***note to the Chief tailgaters/fans going to the game***).

I don’t want to get too much into the snow aspect…it’s too far away and would require the perfect timing of a disturbance and the influx of arctic air into the area…which may try to dry out the moisture as it streams this way. So a lot of moving parts here…but the overwhelming cold theme is a virtual lock. It’s just a matter of how cold…will there be snowpack here or nearby afterwards and how that affects things from there.

That’s enough for today. Our feature photo comes from Margaret Norcorss…just spectacular!

15403859_10153980024431681_5436975346317281205_o

 

Joe

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s