Joe’s Weather Blog: Tracking the snow chances…and the cold…and the rain…not the warmth (MON-11/5)

Good Monday. It’s going to be a raw and chilly morning and early afternoon in the region today. Tomorrow might be a little better but I updated the forecast last night showing the potential of an east>west line of rain/showers developing in the afternoon…around the KC area …then there is the Thursday situation…and the cold…and the potential of record lows (or getting very close to them) and then perhaps more cold…what there isn’t much of…is warm weather.



Forecast:

Tonight: Clearing out and chilly with lows around 40°…some fog is likely too

Tuesday (Election Day): Increasing clouds and cool. Rain chances go up in the afternoon and early evening although not all will get rain tomorrow. Highs in the 50-55° range

Wednesday: Decent but chilly as a cooler air mass moves into the area. Highs in the 40s

Thursday: Snow or wintry mix possible. Highs only in the 30s. Accumulations possible



Discussion:

My goodness the next couple of weeks will be interesting around these parts…I’m not sure if Thursday will be our last snow chance either. There is going to be a rearranging of the pattern into the middle of the month as a big ridge pokes way up towards Alaska and western Canada. When that happens, because of the ying and yang of the weather…a big dip typically occurs downstream…and that will be towards the central and eastern part of the country. That means the delivery of some cold (even by early/mid November standards) air into the Plains and eastern 1/3rd of the US. IF this was the same pattern in the winter…it would be bitterly cold air being sent towards the central and eastern US.

It’s a pattern that will moderate in time…but until then…you’ll be pulling out the sweaters and coats more than the shorts.

Will you pull out the shovels too? Tough to say…but you may want to at least eye-ball where it is in the garage…just in case. At least for Thursday.

Let’s backtrack and deal with today…here is radar.

This rain will only last about 4-6 hours or so…

and that’s confirmed by the short range model called the HRRR.

Tomorrow afternoon and evening a weird little but decently strong and fast moving wave is going to fly eastwards near the I-70 corridor..this may create additional rains too. That’s why I updated the forecast last night to include some rain chances. The EURO model actually caught this on Friday and Saturday…it was indicating something was going to come out of KS and come this way…

I bring this up because the EURO is still the most bullish with the snow potential on Thursday and it still is.

There are a variety of models that I look at to think about what could happen 3-7 days out (or longer). Some TV weather folks (and others for that matter) just look at the GFS model and assume it’s God. There are some meteorologists on TV that I know pretty much their exact forecast because I saw the GFS model and know that’s their forecast.

Some meteorologists just look at perhaps the GFS and the EURO…OK doing better there. Then there are others that look at everything…count me in on that. In that time frame…the GFS and the ensembles…the EURO and the ensembles…the Canadian model and it’s ensembles…the new and soon to be GFS (the FV3) and a few other models as well. When you look at all of this information and then see what is realistic and what isn’t and know the track record and the bias’s of the model data…then you sort of get an idea of “more likely outcomes” than less likely outcomes…and really when forecasting 4+ days away I think this is the best approach.

I tend to look the hardest at the EURO and it’s ensembles for guidance. The GFS and soon the model that’s going to replace it the FV3 model have tendencies to get a whiff of something possibly happening…then lose it for several days…then find it again. For example…the system on Thursday. The GFS was sniffing this (and the EURO too) late last week. Then, as is somewhat typical, it lost most of it over the weekend…then last night it started to find it again. Models that are more consistent with features (and by no means is the EURO perfect either) are models that can be “digested” a bit easier and tend to be more stable.

Really though looking at the ensembles, which are multiple runs of the same model with different physics and initializations, are the better way of going about things…and many meteorologists don’t bother with that aspect of trying to forecast. Hence you see wildly changing forecasts day in and day out when the weather is changeable. November is a changeable month.

Not sure why I went on that tangent but I know a lot of students in weather read this blog to learn more about the weather and forecasting…so maybe it will at least open some eyes for others to think about improved ways to forecast and at least get better ideas of what’s coming.

So let’s talk about Thursday.

Colder air starts moving into the region on Wednesday. As this occurs into Thursday the atmosphere will get colder. Several things are going to happen on Thursday. 1) will be the continued seepage of cold air into the region. 2) just how persistent is that and how dry will the air mass be in the lower 10,000 feet as moisture starts streaming in in the mid and upper levels of the atmosphere on Thursday will play a role in all this. 3) how strong will the jet dynamics be to create snow towards the west of the area…remember yesterday I showed you where we were going to be on the jet stream diagram I created…will be be in a region of favorable “lift”? 4) will the lift be lasting enough to create enough snow to overcome the initially dry air in the lower part of the atmosphere? 5) if so how long and when exactly does the snow start and end. 6) daytime snows in November (unless it’s pouring down) can be tough to accumulate on pavement because of the pavement temperatures. 7) does the snow linger long enough after sunset and hard enough to create pavement issues and 8) can the whole thing be just too weak to generate much more than curiosity (it’s snowing!!!) flakes and not a lot more.

So obviously there are a lot of things going into Thursday’s situation that are still “up in the air”. Let’s not downplay things…let’s not cancel plans at this point…it’s just too soon. It needs to be monitored because it should snow…and I’m not as concerned about the “coldness” of the atmosphere as others are..I think it will be cold enough for a mostly snow event. With the surface temperatures be under 33-34° though…that could be a tougher nut to crack. That’s important because it’s really tough to get an accumulation here when the temperatures are much above that unless it’s really coming down.

Back to the model data…let’s recap the snow chances off the data:

EURO…yes…EURO ensembles…yes…EURO control model…yes. GFS…now back on the snow train in today’s data…GFS ensembles…just barely (earlier today)…Canadian..yes…Canadian ensembles…yes…FV3…yes…and since we’re now in the NAM model range…not much at all but flakes.

So a lot of data suggests that snow would be a reasonable forecast for Thursday. The models do vary in terms of the amounts of snow…and just looking at snow maps off the model data is silly…because of the snow timing (day mostly) and the fact that the models may not take into account any mixture of the precip that is also possible depending on the atmospheric profile.

The bottom line is that we need to be aware of things and remember that accumulating snow is certainly possible in my opinion on Thursday. I wouldn’t change any plans at this point though…that can wait till tomorrow or Wednesday.

Our feature photo of the day is from Ronald Ziolo…yesterday was a stunner. The sun was dropping in the sky at around 4:45 or so…and it was illuminating the bottom of the clouds that were moving away and the tops of the trees which, in some cases, still have some nice color towards them. It was stunning to see!

One of my favorites of the year!

Joe

 

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