Tag Archives: Rain

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.

HEAVY RAIN EXPECTED TOMORROW INTO SUNDAY

As discussed yesterday, we are still expecting a heavy rain event to affect the area beginning tonight and lasting into Sunday. A Flash Flood Watch has already been issued for the entire forecast area by the National Weather Service office in Fort Worth. The graphic below depicts what we can expect in terms of rain amounts by the end of this event. On average, 3 to 6 inches of rain is expected across our area with locally higher amounts possible. This will only exacerbate the extraordinary rainfall received this year and flooding and flash flooding will be of major concern.

Post Christmas 2015 heavy rain event. Map depicts expected rain totals by the end of the event.

RAINFALL RECEIVED ACROSS THE AREA

Below is a snapshot of rain totals received since our rain event began yesterday, December 12, 2015. Overall forecast values were a little bit lower than forecasted for the central portions of the Metroplex. Western sections did well by staying at an inch or less. Eastern sections stayed between 1 and 2 inches, and the much heavier rains were east of the forecast area as predicted. Of note, Gainesville, TX has hit a whopping 80 inches of rain for 2015 – truly incredible!

Rain received across the forecast area as of 7:00 am December 13, 2015.

IT’S OFFICIAL – DFW RECORDS ITS WETTEST YEAR OF RECORD

Out of 117 years of weather records, dating back to September of 1898, DFW records its wettest year on record officially today. With 55.30 inches of rain (as of 8am on Friday, November 27, 2015) this shatters the old record of 53.54 inches set in 1991 with the month of December left to go.

HEAVY RAIN POSSIBLE ON THURSDAY…LOWS IN THE 40s THIS WEEKEND

Our next storm system, that will affect our weather, is currently moving from down from the Pacific northwest. It will move as far south as Nevada before opening up and moving east across the Plains. Ahead of the upper-low, moisture will begin advecting into our area, indicative of the mostly cloudy skies today. Showers and thunderstorms will begin to overspread the area as early as tonight and become widespread on Thursday into Thursday night. There is some marginal instability with this system and very high shear, thus we cannot rule out one or two severe storms with moderately sized hail, but overall widespread severe weather is not expected with this system. However, PWATs are expected to climb to 2 inches by Thursday. This will allow for storms to produce heavy rainfall. So by far our biggest threat with this system will be heavy rainfall. Since our grounds are saturated and cannot hold anymore water, the National Weather Service in Fort Worth has already issued a Flash Flood Watch for nearly the entire forecast area. Widespread 1 to 2 inches look like a good bet with this system with isolated higher amounts.

A cold front will move across the area behind this system early Friday. This front will bring a little chill to the air as it has some Canadian air behind it. Thus, morning low temperatures are likely to dip into the 40s for the first time this year at DFW Airport over the weekend with highs struggling to make it into the 60s on Sunday. The models continue to hang back some energy for the weekend. Thus, after a dry day on Friday, low end POPs are warranted for Friday night into Saturday for some light rain in the cooler air.

We are watching another storm system for early next week that has the potential to bring more showers and thunderstorms to DFW. A stronger cold front may be on tap for later next week.

OCTOBER 2015 THE 2ND WETTEST OCTOBER ON RECORD

October 2015 has come in as the second wettest October on record. The top five wettest Octobers are:

1981 – 14.18 inches
2015 – 9.82 inches
1919 – 9.44 inches
1991 – 9.32 inches
1959 – 9.22 inches

This brings the total for the year 2015 to 48.93 inches of precipitation, making it, so far, the sixth wettest year in DFW weather records.

October 2015 came in with a mean average temperature of 71.2°F, making it the 12th hottest October on record. This puts the year 2015 so far in the running, with an annual average mean temperature of 69.3°F, as being the hottest year on record for DFW.

MAJOR RAIN EVENT TODAY TO SUNDAY [UPDATED]

Setup for major rain event unfolding for DFW for Thursday through Sunday. Map courtesy of the National Weather Service, Fort Worth, Texas.

UPDATE: It appears that everything is lined up for two episodes of heavy rain, one tonight into tomorrow, and another tomorrow night into much of Saturday. Forecast rain amounts, when all said and done, will be a widespread 3 to 6 inches of rain across the forecast area with isolated amounts approaching, or even exceeding, 10 inches. It is too hard to determine where the heavier, narrow bands of really intense rainfall will setup, or what areas will see the most training of storms, but these are the areas that will receive the most amounts of rain. A Flash Flood Watch has already been hoisted by the National Weather Service office in Fort Worth that includes all counties covered by this website. Please stay alert to changing weather conditions, and remember, don’t drive your car into flooded roadways.

It has been quite some time since DFW recorded multi-inch rains or had a protracted rain event, but it appears the ingredients are coming together for a major, protracted rain event later this week. An upper-level low is going to slowly eject east northeast from the desert southwest onto the plains. As it does so, tropical moisture gathering near the Yucatan (was once projected to form into a tropical system by the models, now will not) will be advecting northward into North Texas. In addition, what will be a named storm, Patricia in the Pacific, her remnants and moisture will get absorbed northward into Texas this weekend allowing pWATS to climb to 2 inches, a good two standard deviations above normal for October. Another disturbance will quickly move in on the heels of the desert southwest upper-low dragging a cold front with it providing additional lift Saturday and Sunday. All this points to a heavy, protracted rain event beginning as early as Thursday and lasting through Sunday for the forecast area. It is too early to nail down just how much rain we will receive, but indications are that this will be a widespread multi-inch rain event for the area.

PATTERN CHANGE TO BRING RARE SUMMERTIME COLD FRONT TO DFW

The synoptic, upper-air pattern will begin a change today. Amplified ridging will build along the west coast of the United States and deep troughing will ensue across the eastern 2/3 of the CONUS. This will allow a Canadian airmass to dive south into Texas over the weekend. The cold front should approach the Red River counties of North Texas by tomorrow afternoon. Compressional warming ahead of the front will allow for temperatures to climb into the upper 90s as far south as the I-20 corridor for highs on Friday. Showers and thunderstorms will break out along the front. Rain chances will spread form north to south as the front progresses south. This is not expected to be a heavy rain event as it will be relatively short in duration as the front passes. Behind the front, much drier and subsident continental air will spread in as the surface high builds southward. Temperatures will be a good 8 to 12 degrees cooler behind the front with highs in the 80s and lows in the mid-to-upper 60s. Not bad for June in Texas!

DFW TO SEE VERY HEAVY RAINFALL AS TROPICAL STORM BILL MOVES OVER THE AREA

Tropical Storm Bill is bearing down on the Texas coast this morning near Matagorda Bay. Tropical Storm Warnings are now in effect along the Texas coast. Tropical Storm Bill is currently located as of 7:00 am at 28.2N latitude and 96.0W longitude with maximum sustained winds of 60 mph and a central pressure of 997 mb. It is heading to the northwest at approximately 13 mph. Most model guidance then turn this north toward the DFW Metroplex. The heaviest rains will be to the east or right of the center of circulation as it moves north and eventually northeastward. The latest guidance is unanimously coming into agreement that it will track along the I-35 corridor or just to its west. This puts most of the DFW Metroplex in a position to see heavy rainfall beginning as early as Tuesday evening and lasting through Thursday night. In addition, most of the Metroplex will be in the favorable quadrant to see tropical tornadoes. Obviously with the record rains set in May, our ground will not be able to absorb a lot of additional rainfall, thus Flash Flood watches are already in effect for all of the forecast area as both flash flooding and flooding will be possible. Widespread 4 to 6 inches of rain will be possible in and around DFW with locally 8 to 12 inches possible where the center of circulation tracks and where any heavier rain bands train. Residents of North Texas should stay alert to the latest forecast regarding this hazardous weather situation.

National Hurricane Center latest track on Tropical Storm Bill