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.
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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.
CURRENT CONDITIONS NOW WORKING
The site is happy to report that the “Current Conditions” section on the main page is now reporting all data correctly. We apologize for the downtime. A big thank you goes out to Curly at Michiana Weather for his help in resolving the issues. Please check his very nice weather site out.
CURRENT CONDITIONS NOT REPORTING ALL DATA
The current conditions panel is not reporting all data correctly. The most obvious is that the current condition icon is not displaying. We are having an issue with the data feed that supplies our panel. We are aware of the problem and working to resolve it.
HEAVY RAIN RETURNS AS SPRING THUNDERSTORMS FIRE FOR THE FIRST TIME
The coming week is going to be a wet one for much of North Texas, including the DFW Metroplex. A very big upper-level low will be sinking south into Mexico and then ejecting east northeast slowly. The slow movement of this system will allow abundant moisture to stream into the region ahead of it. This is already noted with overnight low temperatures well above normal for this time of year.
Showers and thunderstorms will begin to fire tomorrow along a dryline in West Texas. At the same time a jet streak will be out across the Texas and Oklahoma panhandles juxtaposing North Texas in the right entrance quadrant of a speed max which will enhance lift across the area. Some hi-res models are forecasting convective development tomorrow as far east as the I-35 corridor. All storms that form should be supercellular in nature and elevated. With 1500 to 1800 J/Kg of convective potential energy, or CAPE, available, some of these storms could be strong to severe. Large hail would be the primary threats. In addition to the severe threat, heavy rainfall will also be possible as precipitable water values, or pWATS, climb above the 99th percentile for March. This could greatly enhance rainfall rates.
Monday night into Tuesday morning models are showing an MCS (mesoscale convective system) moving across North Texas with the potential for very heavy rainfall. The outflow boundaries from this system could act as foci for additional storm development on Tuesday as widespread lift begins to encroach on the area as the upper-level low begins moving east northeast. The MCS could also serve to help stabilize the atmosphere on Tuesday which would help alleviate the severe weather threat. While it is too early to pinpoint the mesoscale environment on Tuesday, it does appear all modes of severe weather will be possible on Tuesday, including tornadoes. A dryline will sharpen west of the Metroplex and act as focus for storm development as jet streak lifts out of the lower Rio Grande Valley. In addition to the severe weather threat, heavy rainfall will also be likely given the high pWATS. It is possible that Tuesday could see the daily rain record broken.
A weak cold front will push through ending the severe weather potential, but not the rain. Overrunning showers will likely continue. The remainder of the week looks to remain wet through Friday as north and central Texas remain on the eastern flank of the upper-level low. There won’t be significant drying until the upper-low moves far enough east by the weekend to end all rain.
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.
DFW WEATHER NEW MOBILE PAGE
A new mobile page for the site was launched over the weekend. We have redesigned it in jquery with collapsible sections. It contains everything the old mobile page did, and eventually, we will be adding to that. Also, the page features a new 7-day forecast grid that now contains wind data. It will also give you the detailed forecast for the particular day if you hover your mouse (or tap on the icon if on a mobile device) the weather icon. We are working to port the new grid over to the main desktop website. It will replace the 2-Day Outlook section on the home page. The page can be accessed from the main site via the left hand navigation menu, or by accessing the site via a mobile device, you will be automatically routed to the mobile page.
WEBSITE UPDATES/CHANGES
Several new updates and changes are being implemented to the website. The first is the weather alerts system has been upgraded. It now features an interactive Google map highlighting the area affected by the advisory. It will also now list all active advisories in the top alert box on the home page, followed by which counties are affected by each advisory. If you click on the counties listed, you will get the details specific for that county regarding that advisory. Additional tweaks to this upgrade are also being worked on.
The other change was to combine the detailed forecast page with the 7-day forecast page. So you will have the complete 7-day forecast grid at the top of the page followed by the daily detailed specifics below that. There will no longer be a separate page for the detailed forecast.
We are also working on an upgrade to the graphical 7-day forecast layout grid for the 7-day forecast, as well as replacing the current conditions dashboard on the home page with an upgraded interface. Future updates may also include a revamped mobile page.