HOTTEST OCTOBER AND HOTTEST YEAR ON RECORD FOR DFW?

So far this October, the mercury at DFW Airport has officially not fallen below 50°F. Given the weather pattern out through the end of the month, it is pretty much a lock that we will not fall below 50°F before October is over. There has only been four other years in weather recorded history that the temperature failed to fall below 50°F, 1947 (53°F lowest), 1950 (51°F lowest), 2004 (51°F lowest), and 2015 (51°F lowest). In addition, October 2016 is on track to be the warmest October ever recorded with a mean running temperature of 74°F (through October 28th). The entire year of 2016 is currently on track to be the hottest year in DFW weather recorded history with a mean temperature of 71.7°F (through October 28th).

FIRST DAY OF AUTUMN TODAY – BIG CHANGES ON THE HORIZON

UPDATE: The forecast below is largely unchanged. For this update though, the frontal timing will be adjusted a bit to reflect the latest data. The front is now expected to move across the DFW Metroplex on Sunday in the late morning to early afternoon timeframe as opposed to Sunday night. We are still expecting a decent rain event into early next week, with rain chances now extending into Tuesday. There should be widespread totals by Monday of 1 to 3 inches of rain with locally higher amounts possible.

Although today is the autumnal equinox, it will still feel like summer with above normal temperatures with highs well into the 90s continuing today. Though, we should thankfully not see any more triple digit heat like earlier this week. However, there are some big changes coming our way.

  • Moisture will begin to increase tonight in response to storm system forming out west.
  • Showers and thunderstorms will be on the increase tomorrow, mostly along and south of I-20, in response to the storm system moving out of the Rockies onto the Plains.
  • Showers and thunderstorms become more widespread on Saturday through Sunday.
  • PWATs increase to 2+ standard deviations above normal, setting the stage for bouts of heavy rain Saturday night through Sunday.
  • Strong cold front expected to arrive Sunday night (though timing could change). This will be the first significant cold front of the fall season.
  • Discrepancies between the ECMWF and GFS models, with the former cutting off energy and hanging it back, dictate when precipitation will shut off, regardless substantially drier and much cooler air will move in behind the cold front. Rain may linger into Monday per ECMWF which may effect degree of cooling of temperatures.
  • Widespread 1 to 3 inches of rain expected by Monday with locally higher amounts possible.
  • Temperatures behind the front should cool to the 50s in many areas for the first time this season with highs in the 70s.

The forecast could obviously change given the discrepancies among the ECMWF and GFS, especially with ending of rain and amount of cooling of the temperatures behind the front. Overall, the theme of a wet weekend and much cooler weather early next week is looking likely no matter which solution verifies.

ANOTHER 100 DEGREE DAY AT DFW AIRPORT – FALL COOLDOWN ON THE HORIZON?

Yesterday, the mercury hit 100°F at DFW Airport on southwesterly winds. I really thought we would get through the rest of our hot season without hitting triple digits one more time, as that wasn’t readily apparent in the overall synoptic pattern. Today, the winds should be more southerly/southeasterly, H5 heights a little lower, and H85 temps a degree cooler as a result. This may help to keep temperatures below 100°F today, especially with the 0.35 inches of rain received yesterday at the airport, but it will again be close. Heights over all should continue to weaken as we head through the rest of the week. Moisture will begin to advect northward on Thursday, thus after another hot day on Wednesday, temperatures should be slowly coming down.

The guidance (both the GFS and ECMWF) are coming into better agreement with the pattern for next week with more rain opportunities beginning as early as this weekend. Both show the first significant cold front of the autumn season next week, but with slight timing differences. This is something I have been watching since the cool down earlier in the month didn’t pan out, and I suspected that our next big shot at cooler air may come the last week of September. The ECMWF weeklies have been locked on to this for a while now. This will be something I will have more details on through the week as better data become available. It should be noted that if the current guidance holds, it will be significantly cooler to close out the month of September.

DFW OFFICIALLY HITS 100°F FOR THE FIRST TIME THIS SUMMER

On July 22, 2016, DFW Airport records its first 100°F temperature of the 2016 summer season. The average first day for triple digit heat is usually around July 1st. The above normal precipitation, both year-to-date and since last year, has kept soils moist and greenery unusually lush well into July. In conjunction with strong summer ridging, which has largely been centered in the desert southwest part of the CONUS this summer, has prevented temperatures from being too terribly hot by Texas standards. We may again flirt with the century mark today, but temperatures will be coming down as the ridge retrogrades back west from troughiness diving into the northern part of the country. This will allow some rain chances to creep back into our forecast next week and temperatures should stay below the century mark for much of next week.

IT’S JULY 4TH AND DFW HAS NOT REACHED 100°F YET

It’s July 4th with 1/3rd of the summer behind us, and it has not officially hit the century mark at DFW Airport this season. What gives? Well, the average date for the first triple digit reading at DFW Airport is actually only July 1st. There are several other factors that have kept us below the century mark so far.  For one, we have seen above normal precipitation to date. This collects in the ground and keeps the grounds from drying out like it normally would this time of year. The increased precipitation has also kept things greener than normal. The evapotranspiration effects (the process by which water is evaporated back into the atmosphere from the soil and plants) actually helps to slow the temperature rise while also providing more humidity which makes it feel hotter than it actually is outside. Another reason the temperatures have largely remained below 100°F is that the typical summertime ridging has largely been centered out to our west across the desert southwest. It has been very hot in this region so far this summer. The influences of this ridge has so far been pretty minimal compared to other summers. North Texas has actually been caught between the ridging out west and troughing over the east, and this has provided for more northerly/northwesterly flow aloft patterns than is typical during summer. This has actually allowed more opportunities for rain as disturbances move into our area around the ridge. So, given that DFW Airport picked up another nearly 2 inches of rainfall overnight, the ridge not fully building in strong keeping heights lower and H85 temps not as warm, and a breezy pattern at the surface keeping the boundary layer well mixed, the chances of seeing 100°F at DFW Airport over the next few days seems pretty unlikely. Highs will continue to top out around 96°F to 98°F with heat index values between 103°F and 105°F.

SIGNIFICANT SEVERE WEATHER EVENT UNFOLDING FOR THIS AFTERNOON

Residents of North Texas, and in particular, residents in the forecast range of this website should be paying attention to the weather this Friday, April 29th afternoon. An extremely unstable atmosphere has setup shop across the area with excessive CAPE values of 3000 to 4000 J/Kg. A warm front has moved north of the area near a Bowie-McKinney line and has become stationary with a dryline extending southwest back toward Abilene. A surface low/triple point was noted between Snyder to Seymore. This dryline is expected to push eastward in response to height falls across the southern Plains. Showers and thunderstorms will begin firing along this dryline this afternoon and will very rapidly become severe. Initially these storms will be discrete supercells and be capable of producing all modes of severe weather including tornadoes. The convection will congeal into a squall line as the event progresses and march eastward away from the area by evening. The following hazards will be possible with this event:

  • Very large hail to the size of softballs
  • Damaging straight-line winds
  • Flooding
  • Frequent lightning
  • Tornadoes

A Tornado Watch will likely be issued shortly. Residents of North Texas should keep advised of the latest weather watches and/or warnings and be prepared to take action.

HEAVY RAINS RETURN TO DFW

A very wet week is in store for our forecast area. A powerful upper-level storm system is currently setting up shop out in the desert southwest and will become a cut-off low taking its sweet time to move eastward this week. As a result, several rounds of showers and thunderstorms will be possible across the area beginning early tomorrow morning and lasting through much of next week into next weekend. Very heavy rainfall can be expected, especially tomorrow into Tuesday, as precipitable water values (PWATs) climb to 1.45 inches around the 75th percentile for April. There is an attended severe weather risk tomorrow into tomorrow night, but most of the severe weather should stay south of I-20 into Central Texas. The main threats will be large hail and damaging winds in addition to flooding. The tornado risk will be highest the further south you go, but not zero in our neck of the woods. The big story will certainly be the amount of rainfall. A Flash Flood Watch has already been issued by the National Weather Service office in Fort Worth for the entire forecast area for widespread 4 to 6 inches of rainfall with sporadic amounts to 8 inches plus by Tuesday morning. Residents of North Texas should begin making preparations for flooding conditions. Remember not to drive across water covered roadways.