Tag Archives: heat

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.

FIRST SIGNIFICANT CHANCE FOR RAIN IN A WHILE AT DFW

It is looking like our first significant chances for rainfall at DFW will materialize by Sunday into Tuesday as a cold front and upper-disturbance approaches the region. Until then, we must contend with strong ridging over our area with gusty southerly winds. Combined with dried fuels, low humidity, and near record warmth, these strong winds will present elevated fire weather concerns, especially west of the I-35 corridor where Red Flag Warnings have been issued. The strong winds today will gust to near 40 mph at times, as a result, the National Weather Service in Fort Worth has issued a Wind Advisory for all of our forecast area. Temperatures will warm some 15 to 20 degrees above seasonal normal values with highs approaching or exceeding 80°F today and tomorrow. Overnight lows tonight will be near our normal high temperature for this time of year, struggling to get below 60°F, if at all.

The ridging should begin to relax on Saturday transitioning to more zonal flow aloft. This will allow the trough and cold front across the Central Plains to begin slowly sagging southward. This front will move across our area rather slowly beginning on Sunday. As it does, a disturbance will move across enhancing lift across our area which will enable showers and thunderstorms to fire. The best chance of rain will be along and behind the front as it moves through Sunday night into Monday. The highest moisture will be along and east of the I-35 corridor, thus this is where the best chances reside for receiving the most rainfall with this system. It is too early to say with confidence exact amounts, but we could be looking at widespread 1 inch plus amounts along and east of the I-35 corridor, especially with PWATs expected to climb as high as 1.50 inches.

RECORD HEAT AGAIN TODAY AND TOMORROW AT DFW

The record high for DFW for today, October 14th is 99°F set in 1910. The record for tomorrow, October 15th is 92°F set in 1999. Forecasted temperatures are to be in the 97°F to 100°F range for today and tomorrow. Likely making both records in jeopardy. The hottest day will likely be today given the strength of the overhead ridge and the southwest/westerly downslope components to the winds. If we reach 100°F today, it will set an all time record for the latest DFW has ever hit the triple digits by a wide margin. That would truly be an incredible feat! Given that is almost a 40°F diurnal temperature difference (extremely rare for us), and more characteristic of a desert climate,  means we will probably stay just under the century mark. Tomorrow should be a degree or so cooler as the upper ridge weakens a tad, but the record is only 92°F, and that is a certainty it will be broken, as forecasted highs will be in the upper 90s, yet again. A cold front is on tap for Friday, but given how dry we are ahead of it, it will not produce any rain. However, it will lower temperatures significantly over the weekend with lows in the low 50s and highs struggling to reach 80°F, making for a truly nice autumn weekend. A stronger trough and system looks promising for the middle of next week for the best rain chances in awhile and a more significant autumn cool down, but more on that later.

NEAR RECORD HEAT POSSIBLE NEXT SUNDAY AND MONDAY FOR DFW

The record high temperature for DFW for Sunday, October 11th is 99°F and for Monday, October 12th is 97°F. Current forecast models are predicting high temperatures approaching 100°F across the area on these dates. If temperatures were to actually hit 100°F at DFW, it would not only be the hottest temperature for these dates, but also the latest on record that we have ever hit the triple digits. Currently, the latest we have ever hit triple digits at DFW is 106°F set on October 3, 1951. Currently, it looks as though temperatures may stay just below the century mark on both dates, but records could be tied or threatened. This is definitely some hot October weather!

SEPTEMBER 2015 AMONG HOTTEST ON RECORD FOR DFW [UPDATED]

UPDATE: September 2015 is officially the 5th hottest September on record for DFW. The top 5 hottest Septembers are as follows:

  1. 2005/1939 – 83.7°F (average monthly temperature)
  2. 1998 – 83.6°F
  3. 1931 – 83.0°F
  4. 1933 – 82.8°F
  5. 2015 – 82.7°F

September 2015 is shaping up to be among the hottest Septembers on record for DFW. The hottest September occurred in 1939 and 2005 where the average temperature for the month reached 83.7°F. Currently, this month, so far, is third hottest with a current average temperature of 83.5°F. The second hottest September is 1998 with a monthly average temperature of 83.6°F. There is no indication of a significant cool down between now and the end of the month, thus 2015’s chances of remaining among the hottest Septembers on record is quite high. However, it isn’t likely for us breaking the 1939/2005 record, based on forecasts through the end of the month.

THE HOTTEST WEATHER OF THE SUMMER FOR DFW THIS WEEKEND INTO NEXT WEEK

Although we have enjoyed a rather average summer thus far here in DFW due to near record rainfall, residents should get ready for the hottest weather of this summer coming this weekend into next week. The upper-ridge that has been located in the desert southwest the last few days is expected to head east, strengthen, and expand centering itself over North Texas. As a result, temperatures are expected to steadily increase daily through early next week topping out in the 103°F to 107°F range across the area. This will come pretty close to record levels at DFW Airport for early next week. In addition, increase of moisture will push heat indexes in the 105°F to 110°F range making for the hottest conditions of this summer season. Heat Advisories will likely be issued for the entire forecast area later this week. People should curtail outdoor activities to morning or early evening to avoid heat exhaustion or heat stroke. However, even though rain is not expected anytime soon, the near record El Niño in the equatorial Pacific will almost ensure a return to much wetter conditions this fall.

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

DFW Airport, the official climate site of record for the DFW Metroplex, finally hit 100°F yesterday. There will be multiple more chances of triple digit heat through Thursday before a weak cold front knocks temperatures back down into the mid-to-upper 90s for Friday and Saturday. The ridge that has been dominating our weather the last few weeks is expected to re-orient itself across the desert southwest opening up the door to northerly/northwesterly flow aloft across North Texas. This will help drive a weak frontal boundary into our area later this week. Scattered showers and thunderstorms will also be possible along the boundary. The upper ridge is then expected to migrate eastward back towards Texas which will pump up the heat again early next week.

For those wondering, no this is not the latest first 100 degree day of the season in Metroplex history. 1973 and 1906 both saw zero 100 degree days the entire summer. We typically average about 16 days of 100 degree heat in most summers, and the hottest average temperature is 97°F. We do have a significant El Niño that has developed in the equatorial Pacific. The interesting thing about this El Niño, unlike others, is the unusually colder waters in the northern Atlantic, the area of the central Pacific where the highest heat content is positioned (more west based), the unusual amount of warm waters along the west coast of the CONUS stretching into the Gulf of Alaska. All of these factors will play a role in the upcoming winter season in determining mean position of ridges and troughs and storm tracks.