DFWWeather

The pattern so far this season is for all the models to have deep cold air and then back off as we get closer to the cold spell. I already see this trend starting to happen in all of the 6z models with this New Year's Eve event. While the track of the upper low is ideal, the source region and the depth of the cold have been questionable from the get go on this event. There is no true Arctic air involved. We will see how the models trend as we get closer. My gut feeling for DFW is that this is a cold rain with maybe a few sleet pellets or snow flakes mixed in. We have a decent stratospheric warming event taking shape and 50/50 teleconnections in our favor (-AO, +PNA, -NAO) for developing Arctic cold in about 7 to 10 days. Time will tell if this can translate into some verifiable cold air. We have only hit 28°F at DFW as the coldest low and the winter is 1/3rd over.

Record cold temp set this morning at DFW of 55°F. The old record was 56°F set in 1941. If we fail to rise to 70°F (which will be close), then I believe another record will be set. Turns out none of the models handled this cold front well at all with the ECMWF bias of hanging back too much cold air in the west as clearly evident (though it does get props for being the only model initially to show a cut-off low forming). However, that model was way too warm. Dense cold airmasses like this rarely ever get hung up out west and then retreat north as depicted on that model (extremely rare and bizarre case if that ever happens). The NAM was the only model to get it some what right, but it was even too warm on its low temps for DFW. The earlier temp forecasts of the GFS/ECMWF/GEM last weekend of 50s here was correct before they all went way too warm.

Lows can fall into the 50s at DFW any month during year if conditions are right. In fact, they have fallen into the 40s in June before. Technically, we are in autumn, though not by traditional calendar standards as what most people call autumn. Meteorological fall starts September 1st. In meteorology, fall temperatures are measured from September 1st through November 30th. It has been as cold as 40°F in the month of September before at DFW. What will be far more interesting is the prospects for snowfall in the Panhandle behind this front and threat of freezing temperatures. If snow does fall, it will be the earliest ever recorded in the state of Texas and by a wide margin (record held by Stratford, Texas on September 27, 1936). A snowfall this early would truly be unprecedented. Also, any freezing temps reached would be the earliest on record for the state. This cold airmass really means business. Some models are still showing lows perhaps reaching 48 to 50 at DFW. If we fall into the 40s, it would be the earliest on record. Both daily low temp and low maximum temp records are in jeopardy both Wednesday and Thursday at DFW behind this cold front. This is really like a once in 100 year cold air outbreak.

After reviewing incoming 12z data, I'm not so sure. I think if anything Tarrant County will be downgraded to a Winter Weather Advisory or removed from the Winter Watch/Warning altogether. There is no supporting evidence on the models to have added Tarrant to the watch in the first place (and I am still perplexed on the reasoning on that), and certainly not Dallas County. This is primarily going to stay north and west of the Metroplex. Interesting to note on the the latest NAM 2m Temps of below zero over the deep snow pack just northwest of Wichita Falls.

12z GFS is even more bullish with 7.0 inches at DFW Airport to over a foot of snow in southwest Tarrant to hardly any in southeast Dallas County with over a quarter of an inch of sleet/ice for the entire Metroplex. Low temperature of 23°F at DFW Airport during the coldest part of the event. I don't see that trend, if anything a southeastward shift of heaviest precip.

Yes, but all of the GFS ensemble members output snow/ice for the area and over 50% of the both the 0z and 6z ensemble ECMWF members also produce significant accumulations of snow/ice for the area as well as a majority of Canadian ensemble members. The deterministic GFS is not an outlier in that respect. This is something to really watch. None of the models have done well with cold air this winter season at all and the trend here is colder. The 500mb pattern is one favorable to produce significant to even major snow/ice events in North Texas. The question is moisture/lift at the time of the coldest air and how cold the air will be. With it being nearly 80 today, temps will need to be in the 20s for this to really stick to the roads. Some models have us in the 20s for the event. The NAM is discouraging as it is cold enough, it just dry slots us, however it is know for being too dry in that time range. This is certainly the best setup I've seen in years for us.

I can't either! The ECMWF and the GFS though don't seem to agree on the degree of cold. GFS is warmer and following MJO in phase 1 and 8. Whereas the ECMWF is following the recurving typhoon. Which is correct? Enjoy the relief while it lasts as it looks like we will be back above normal for much of the remainder of October, unfortunately. DFW just had its hottest September on record out of 121 years of weather records. 86°F was the average temp (normal Sept average is 78°F). Though ironically we did not set any high temperature records. We never fell below 70°F which was first for the month and we had the most 90+ degree days of any prior September. It was also the only September on record with no measurable rainfall. Far cry from last year when we recorded 12.96 inches of rain which was the wettest September on record.

September Climate Statistics for DFW: We are approaching the autumnal equinox and DFW Airport has failed to record one single low temperature below 70°F. Looking at the models to the end of the month, it doesn't appear that we will get to 70°F or below anytime soon. Out of 121 years of records, that has NEVER happened. Only 15 years of the 121 year record period have we seen Septembers where the low failed to fall below 60°F which is kinda of a benchmark for a warm September. Roughly 60% of the time, DFW has fallen below 60°F at least once during the month of September. Roughly 30 of the 121 years of records, the temp has fallen to 50°F or below at least one time in September. This September is on track to the be hottest September on record for DFW, and while daytime temps have been hot and slightly above normal, there have not been any daily record highs tied or broken. It is all because of the low temperatures. Normal lows this time of year should be in the 65°F to 67°F range falling to 62°F by the end of the month.

So far, the 2018-2019 winter is the 5th warmest on record at DFW. This is a far cry from all the forecasts calling for temps this winter to be 1 to 3 below normal across Texas. Complete dud of a winter. I wonder if there is still time for us to get some bona fide Arctic air down here? The lowest temps so far this winter was way back in November (technically not even winter) of 25°F.

In all of weather records kept for North Texas area, the above scenario as has never occurred, so that was an easy disregard. Even during the severe Arctic outbreak of 1899 (coldest on record for this area), it wasn't that cold. Nearly all of today's guidance unanimously is backing off on any Arctic air intrusions over the next couple of weeks, despite the -EPO and MJO phases, the abundance of cold air in Canada, and the highly amplified flow H5 pattern. Our best chances to see Arctic air intrusions are this Sunday 2/4 and again around 2/10. I'm not sure I totally buy off on this yet (especially for the 2/10 period), but it is sure looking like most of the cold air will be kept well north and east of Texas this go around. The operational models have not handled any of our cold air intrusions this winter well at all, and it could possibly change.

Officially, the NWS is saying the low today at DFW Airport (KDFW) was 13°F. However, the 5 min metar observations data shows that the site hit 12°F at 5:20 am, 5:25 am, 5:30 am, and 6:45 am. The former we have hit 7 years ago, but the latter would be 22 years. What would be the reasoning on this?

If DFW Airport reaches 12°F or lower as forecasted...then that will be the coldest we have been in 22 years. You have to go all the way back to February 1996 when we hit 8°F. Doubt we will hit the single digits, but we could. This current streak is the longest on record by a wide margin of not falling below 10°F. We are going on nearly 3 consecutive years without any significant snow or ice. Last event was March 4, 2015. By significant I mean 0.25 or greater of ice or 2 inch or greater of snow. If nothing occurs this year, it will be the longest stretch since 1978 without any significant snow or ice for DFW, possibly longer.

I agree, especially given that this is a Holiday impact storm with heavy travel. However, I understand their caution. There is a lot of chaos in the modeling, though, and none of them agree. The deeply negative EPO and the strong MJO phase 7 and 8 argue for deep cold in the southern plains. If we get moisture on top of this, it could get ugly. By the way, I kinda feel the GFS is outperforming the ECMWF this fall. The GFS did a better job with the cold and snow earlier in the month. I think the 0z runs ECMWF is strange hanging the cold up in the Rockies and spilling westward, and delaying it until after Christmas.

I'm liking what I'm seeing in terms of major cold getting here. The 500 mb heights certainly support some massive dump of cold air. Been watching the ECMWF for several runs and it has bee bringing -40°C plus air at H85 into the Great Lakes or just north of there for several runs (I think one run actually on the control got to -45°C). That is quite possibly the coldest air I ever seen on that model. Most models agree the leading edge of an Arctic airmass will make it into North Texas about Friday before Christmas. It is after this they diverge quite a bit. The ECMWF pushes deeper with the trough similar to last time pushing the storm track well south of DFW or North Texas. The latest 6z GFS today is a winter weather lover's dream with nearly 5 days of snow and ice (mostly ice). The 0z wasn't too shabby either. However, this is still several days out and we have been in a massive drought. Like the forecast saying goes, "when in drought leave it out!" Given the upper air pattern I would tend to favor the ECMWF right now. Regardless, the cold is coming, potentially even severe cold!

Glad you brought this up! I've been looking at the same data. Ironically, ECMWF doesn't seem to be quite on board yet with a more slanted trough east of us driving the core of the cold east, which has me very cautious. However, CMC and GFS have been gung-ho about a big cold air outbreak the weekend of the 28th for several runs now as with many ensemble members. Generally, all of next week should be the coolest of this October with the potential of 3 fronts, one this weekend, one about Tuesday, and potential big one the last weekend of the month. All of this will of course be driven by the potential recurve of what should be a super typhoon toward Japan in Pacific. This typhoon should recurve because of the record phase 5 MJO. In fact, the recurve should be a lock! This will drive the 500mb pattern change over North America. Regarding precip chances with this, much too early to tell, I'm not sure on the pattern quite yet.

Today's 0z and 12z ECMWF and the 12z GFS are jumping on board to a major Arctic air intrusion into Texas around Feb 8th time frame. CMC looks like it is on board as well. The MJO looks to be heading to phase 8 about that time. What do you all think?

I know it is on hiatus now, but the cold is definitely coming back in some fashion. Despite the positive PNA, the latest 2mb warming episode over the pole and the epo trending negative towards the end of the month and the NAO trending negative all point to the cold coming back end of next week into week one of February east of the Rockies. MJO in phase 1 and 8? Also, looks like a favorable 500mb pattern for snow and ice for us. Both the long range ECMWF, GFS, and CMC all support this idea. Check out latest 8 to 10 day 500 mb means. Arctic may even overtake the eastern 2/3rds of the CONUS by mid February.

When has there ever been that much rain in a single system in January at DFW? Also, NFWD talks about Arctic front stalling in the area. Again, when has that ever happened in January? The models are either not handling cold air well and it will push on further south, or not make it here at all.

The 0z ECMWF has backed way off on the cold air resulting in nothing more than a cold rain for this event for nearly all of North Texas. It even loses the connection to deep Arctic air. Not impressed with this run at all. 6z GFS is also backing off on the cold air with all frozen precipitation west of the Metroplex during the entire event.

That eastern ridge looks too strong. If we can get that Arctic high underneath the ridge...all bets are off. The ECMWF is known to be too slow in that time range on Arctic air, and doesn't model well the cold air damming process which is clearly evident on the 0z run.

DFW actually for sure hit 15°F, but may have hit 14°F. Waiting on confirmation on that. It is possible for DFW to hit single digits again, I can't explain the 21 year streak though. Statistics say this should happen every four years. Don't forget that we hit -1°F in December 1989 and statistics say we should fall below zero about every 30 years. We haven't seen an cold air mass of that magnitude since. Should it happen again, we definitely would hit the single digits. Had we gotten an inch of snow yesterday, I'm sure we would have fallen to the 10 to 12 degree range. Had we hit 11°F it would have been the coldest in 21 years. UPDATE: The NWS confirmed the DFW Airport low this morning was 14°F, making for the coldest air since 2011. Also, we set a record low max yesterday of 27°F breaking the old record of 29°F set in 1970.

The forecast high today so far at DFW has been 27°F, so that was a good forecast. If this holds, which it will, then that means we set a record cold high as the old was 29°F set in 1970.

I can confirm snow flurries in Arlington and Hust.

The 12z NAM looks dry to me other than some flurries. The ECMWF is just not on board. The problem with this is there is just no moisture. The 500mb pattern is not one that favors snow and ice here. If that little system tracking in from out west could deepen and draw up enough moisture...but unlikely given pattern, especially with Gulf low developing. Those always rob DFW of moisture and we need every bit to make this happen here.

Full McFarland setups are associated with the storm track well to our south, severe cold, and freezing temps into the LRGV (as McFarland wrote about this pattern to be associated with the LRGV most devastating freezes, thus why it was given the name McFarland Signature). While snow and ice can still fall this far north in these setups, it is usually very light as we are so deep into the cold air that it becomes very dry, usually associated with 0°F isodrosotherm well to our south. Occassionally, large storm systems can time with the onslaught of cold air to produce heavier storms right after frontal passage. However, in this case the storm system is held back till Thursday well after the Arctic surge which would mean an unusually far south storm track and we would be well established in much drier air that it would have to fight at that time to get precip to the ground.