DFWWeather

I apologize if I have upset you, but you absolutely did say no more Arctic air for the rest of the season. See your post above from Feb 4th. All I did was disagree with you. I use the word 'extreme' because that is the term the NWS uses. The Extreme Cold Warning is not just for wind chills, it is also issued for the prolonged duration of subfreezing temps, and the threat of temps falling to 10 or lower or for high temps failing to reach 20. For our area, the latter is considered severe cold. In this case, there is a threat some areas around the DFW Metroplex will get to the single digits with this and for a prolonged duration subfreezing temperatures, not to mention wind chills as cold as 10 below zero. I was just pointing out that not even South Texas is escaping the cold. Anytime it freezes in LRGV it is a big deal. That is why Marshall J. McFarland came up with the McFarland signature that recognized prominent 500mb pattern features that lead up to freezes deep into Texas. The key to getting Texas cold is the position of the west coast ridge, if it is along the west coast, or off-shore up over Alaska. The latter has historically produced some of Texas' biggest cold shots and is a key element in the McFarland pattern. Though the current outbreak was not a result of a McFarland.

I guess we just have a different idea of what "extreme" cold looks like for DFW. The NWS has issued an Extreme Cold Warning for the area. Temps are not forecasted to get above freezing until Friday with a shot of getting below 15°F on Thursday morning and wind chills below zero at times tonight and possibly tomorrow night. Subfreezing temps all day this late in the year is quite "extreme." We are talking temperature anomalies of 25 to 30 below normal for a couple of days. I do not know what else you need to have...Feb 2021? What happened in Feb. 2021 is a once in 30 year event in DFW. You said before we were done with the Arctic air for this winter. I said the pattern would deliver, that cold air loves to push in this type of pattern, that it would likely be DFW's coldest air of this winter, and that is exactly what is happening. I might also add they are expecting freezes in the LRGV with this. Freeze Watch in effect for Laredo, Tx right now over to Corpus.

This is not a glancing blow of Arctic air with a ~ 1050 to 1055mb high building down the plains. This is a direct shot. KDFW has a the potential at getting below 15°F with this on Thursday morning with windchills dangerously cold for North Texas. The NWS has issued a Extreme Cold Watch which will likely get upgraded to a warning. I agree precip will be light, but there is a signal in the models for freezing drizzle/mist beyond 4pm Tuesday into early Wed with temps falling well down into the 20s. KDFW is forecast to remain below freezing for at least 36 hours. The deterministic GFS is out to lunch on temperatures and has been performing terribly all winter long for DFW, and doesn't even agree with its own ensembles which are in the teens for KDFW. I think that model just cannot see cold air anymore and there is an extreme warm bias to it. Do not disagree that March may be on the colder side.

This pattern is one that doesn't typically bring North Texas a lot in the way of wintry precipitation. Looking at latest 12z data on all the models, there seems to be a trend of the wave moving east rather quickly being drier overall. Thus, whatever falls will be very light, but I'm starting to think it won't be much of anything. I don't see the type of cold you are talking about without decent ice/snow on the ground, and none of the models suggest amounts would be that much. I think DFW has a shot of getting below 15 with this, maybe down to 8 to 12 with a bit of snow/ice, but it won't anything like 2021, at least for DFW. 10 degrees would necessitate an Extreme Cold Warning for our area though.

Currently, 24°F at DFW this morning with still room to fall. Quite the forecast bust on this airmass as most forecasts had us 27°F to 29°F this morning for a low. The ECMWF has been doing exceptionally well this winter for DFW for temperatures and had us this morning in the low 20s forecasted all week. It should be noted the ECMWF and all of its ensemble members are forecasting 1050+ mb Arctic high to plunge out of Canada into the plains and down into Texas by middle of next week with the coldest air of the winter. Temperatures will easily get into the teens with this (though the deterministic and several ensemble members are suggesting temperatures into the single digits). The other notable thing is the potential of precipitation Tuesday night into Wednesday which would likely be frozen. The Canadian also has signal for precip as does the GFS, the GFS is very light and further east. So I cannot entirely discount the colder ECWMF scenario if we get snow/ice. Looking at our records, for DFW to not have at least one day per winter season dropping below 20°F is actually pretty rare with less than 20% percent of our winters actually failing to get that cold.

Completely agree. I noticed how the FWD NWS has now started to note the potential for low temps in the low/mid 20s for DFW later next week in their AFD. Some of the models/ensembles are showing that temps could even get into the teens. We all know that in this type of setup, the synoptic models do not catch the low level cold air well at all at this time range. That kind of Arctic air loves to push, even against zonal flow in this type of setup. Now whether there is enough moisture at the time of coldest temps for significant icing remains to be seen. While noting the cold bias of the Canadian, its ensembles averages are pretty good, and those are showing the colder potential with this pattern.

Strongly disagree with you. I suggest going back and studying past examples of this same setup. February 1989, February 1996, December 1983 (yesterday 12z ECMWF 500mb closely resembled that), and yes February 2021 as just a few examples. It is known thing to watch for when you see the ridge shift off the west coast and up over Alaska for cold air down into the plains and Texas. MJO moving to phases 7&8 which are cold phases, -EPO, -WPO, -AO, potential -NAO (not sold on that one yet) developing all point to colder air flooding the pattern. Their will be more of southeast ridge that will fight this, but the cold air loves to push in this scenario, and usually down into Texas as opposed off to the east. I'm not saying that we will get anywhere near as cold as those event, just that the pattern is similar and can translate to temperatures well below normal. What is common on these types of setups is usually the models don't catch on until we get right up on the event.

We got a negative EPO, negative WPO, negative AO, and possibly a negative NAO developing next week. Ridge this time positioned off the west coast up over Alaska (big difference this time around as opposed to along the west coast). This time around we may have more of a southeast ridge that will fight. This cold shot would be centered down the plains as opposed to further east. This setup is Katy bar the door cold for Texas. Look late next week to around Valentines Day for a flip to much colder. ECMWF is catching on but having trouble, as it did in Feb 2021 until we got right up on the event. The GFS is also seeing something. While I don't think we will get as cold as Feb 2021, I do think this is going to be Texas' coldest part of this winter coming up.

Analysis of 12z data shows these temps at H85 at DFW at the coldest point of this Arctic air outbreak: ECMWF: -11°C, Canadian: -14°C, GFS: -11°C, NAM: -13°C And shows this for actual lows at coldest point: ECMWF: 22°F, Canadian Ensemble mean: 11°F (deterministic way too cold at 9°F), GFS MOS: 15°F (actual raw number on deterministic GFS is 26°F which way too warm), NAM MOS: 15°F, UKMET and ICON both at or above 20°F The actual forecast low by NWS is 21°F. In past experience with H85 temps -10°C or greater actually translates to mid teens at DFW Airport. Something is wrong, either the H85 temps are wrong or forecasted surface temps on the models and NWS are too warm and are going to bust. The NAM MOS seems the most reasonable to me on temps which does superiorly with low level cold Arctic air in North Texas. Urban heat island usually is not as much an issue in Arctic air as with radiational cooling as we noted quite clearly in February 2021.

For DFW, a dusting to an inch at best if we see snow at all. Concerns of quality moisture making it this far north. All models forecast H85 temps to below -10°C. In my experience, this translates to widespread lows in the low to mid teens, even into the heart of the Metroplex. The ECMWF, UKMET, and GFS deterministic models look way, way too warm with lows barely below 30°F on the GFS and only in the low 20s on the ECMWF and UKMET. Highs will struggle getting above freezing Sunday through Tuesday, if they do at all. Note the ICON and the Canadians show lows in the single digits.

Looks like DFW is in for another blast of Arctic air, perhaps Siberian in origin. This one looks much colder than last week as Texas might take a direct hit. It should arrive this weekend. The 12z ECMWF has H85 temps as cold as -17°C over the Metroplex and similar on Canadian. That would definitely bring concerns of temps getting down to the single digits even into the heart of the Metroplex. There is also the possibility we could stay below freezing for a day or two. However, the models are starting to trend drier with this and don't see much wintry precip with this outbreak. I don't think we will get as cold as February 2021 without ice and snow.

DFW has a current temp of 30°F (fell from 36°F earlier this morning since precip began) with moderate sleet coming down. It will be hard for temperatures to rise if we saturate out below freezing with on going precip. Could be more significant sleet as noted by NWS before change over to all snow later.

The 12z ECMWF ensemble 51 member mean average snowfall for DFW is 8 inches. Remarkable! Its temps are significantly colder than the NWS office. It has a low of 20 for Friday morning and 18 for Saturday morning. All day Thursday it keeps temps between 30 and 33.

The 12z GFS and Candian are upping totals for DFW. Surprisingly, the 12z NAM has increased its totals too. Candian/RGEM going for record breaking snows at DFW 12 to 14 inches. Wonder what the 12z ECMWF will have?

The NWS has upgraded the Winter Storm Watch to a Warning. Going with general 2 to 4 inches with isolated totals 6 to 9 inches. Problem is their forecast temps I feel are much too warm for anything but rain or snow melting on impact. They have a low overnight Thursday into Friday of 34 at DFW. Most models I'm looking at are generally between 30 and 32 during this period.