Dallas/Fort Worth: Heavy Rain Event Christmas Weekend 12/26-28

Christmas Week Forecast Page

➡︎ Heavy Rain Event & Possible Flooding:
Forecast #1 Thu 12/24   ● Forecast #2 Fri 12/25

➡︎ All Christmas Week Updates:
#1 Sun 12/13   ● #2 Tues 12/15   ● #3 Sat 12/19   ● #4 Thurs 12/24   ● #5 Fri 12/25
First forecast is at the bottom of the page (December 13). Updates are posted from the bottom up.

? Tidbit: 2015 is DFW’s wettest year on record (12% above the previous record). View the 2015 total (updates hourly).

rain


Forecast Update: Friday 12/25 at 9:00 am

***Heavy rain event Saturday – Monday AM***
***3 to 5 inches of rain, locally higher***
***Flash Flood Watch in Effect***

◙ There are no changes to my forecast. If necessary, please refer to my previous forecast updates from last week and earlier this week to follow my forecast reasoning. I will include some of those links at the bottom of this post.

◙ I am still forecasting atmospheric precipitable water content to increase rapidly tonight/tomorrow morning, ultimately rising into the 99th percentile for this time of year and even into the top-5 highest values on record for the month of December (based on a 65-year database). Therefore, thunderstorms on Saturday and Saturday night may produce very rapid rainfall rates in the range of 1 to 2 inches per hour.

◙ I believe that there will be an initial round of thunderstorms, followed by a lull Saturday night. Rain will increase in coverage and intensity again on Sunday, lasting through the day/night. The rain will end early Monday with total rainfall amounts in the range of 3 to 5 inches (locally higher). Flooding is possible, particularly in the typical flood-prone, low-lying, and/or urban areas.

◙ High temperatures today will be in the lower 70s. Tomorrow will be warmer, with highs in the mid to upper 70s. The cold front will surge through North Texas tomorrow night, with temperatures in the 40s on Sunday.

◙ There are also no changes to my wind forecast, which I first discussed back on Monday. As the surface low deepens and intensifies on Saturday, the wind will increase. By Saturday night, I expect sustained winds of 25 to 35 mph (gusts to 40 mph) across North Texas.

◙ I believe that Sunday will be even windier, with sustained winds of 30 to 40 mph (gusts to 45+ mph). I wouldn’t be surprised to hear of some wind gusts higher than 50 mph in some locations. A Wind Advisory will certainly be warranted by tomorrow afternoon. If the wind does begin to gust higher than 45 mph, sporadic power outages may occur.

◙ With temperatures in the 40s on Sunday, the strong wind will create a windchill in the 20s. I have a wind chill calculator on my website if you need to use one this winter (bookmark the page): http://www.iweathernet.com/calculators#wind-chill.

◙ A Flash Flood Watch has been issued for most of North Texas, including the DFW metroplex, effective Saturday morning until 6 am Monday. Feel free to use the interactive pan/zoom advisory display on my website. You can click any advisory to read the details: http://www.iweathernet.com/advisories

◙ Some of the thunderstorms Saturday/Saturday night could be strong. At this time, I believe that frequent to excessive lightning and localized areas of damaging winds will be the primary threats.

◙ As I mentioned above, the rain will come to an end early Monday, with high temperatures around 40º. The remainder of next week will be dry with highs in the 40s.

rain

? Return to the top


DFW Heavy Rain Forecast Posted Thursday 12/24 at 10:00 am

***Heavy rain event Sat night – Monday***
***3 to 5 inches of rain, locally higher***

◙ For the past 5 days, I’ve been discussing the vigorous upper-level storm system that will affect the S. Plains this weekend. There are no changes to my forecast. Atmospheric precipitable water content will increase rapidly on Saturday as moisture advects northward from the Gulf of Mexico.

◙ By Saturday afternoon/evening, PWAT will exceed the 99th percentile for late December. Thunderstorms that develop Saturday afternoon/night will be capable of producing rainfall rates of 1 to 2 inches per hour.

◙ Rounds of heavy rain will continue Sunday through Monday morning, with total rainfall amounts at the end of the event in the range of 3 to 5 inches (locally higher). Areas west of the metroplex should be on the lower end of that range (east-west gradient with amounts increasing from west to east). The rain will come to an end by late-morning Monday.

◙ I am still forecasting high temperatures on Saturday in the mid to upper 70s.

◙ The cold front will move through early Sunday morning (before sunrise), with falling temperatures. The high on Sunday will occur just after midnight, with temperatures falling through the 40s during the day.

◙ Temperatures on Monday will stay in the 30s. Monday night will be the coldest night so far this season, and in fact the coldest night since March 6th with lows in the low-mid 20s.

◙ I will have more details forthcoming about the heavy rain event along with a map depicting my expected rainfall totals. I should have that ready by mid-afternoon.

◙ I do believe that a Flood Watch will be warranted by the weekend.

Forecast Summary:

  • Today: Partly cloudy. High in the low to mid 70s.
  • Friday: Mostly cloudy. High around 70º.
  • Saturday: Showers/Tstorms developing. High of 75º to 80º.
  • Saturday night: Rain/Tstorms. Chance of rain near 100%. Wind increasing to 20-30 mph, gusts to 35+mph.
  • Sunday: Rain/Tstorms. Chance of rain near 100%. Sustained wind 25 to 35 mph, gusting to 40 mph. Temps falling into the 40s.
  • Sunday night-Monday: Rain. Windy. Sustained wind 25 to 35 mph, gusts to 40+ mph. Lows Sunday night in the upper 30s. Temperatures steady or slowly falling after the rain ends on Monday.

? Return to the top


DFW Forecast #2 for Christmas Week Posted Saturday 12/19/15

Here is my best guess at temperatures for this week. As predicted in my previous updates, Christmas 2015 will be anomalously warm, with temperatures 15 to 15 degrees above normal.

unseasonably-warm-christmas-2015-in-texas

? Return to the top


DFW Forecast for Christmas Week Posted Tuesday 12/15/15

**Freeze late this week**
**Unseasonably warm from Sunday through Christmas week **

◙ I still expect a dry cold front Wednesday with a freeze Wednesday night and Thursday night. Most of the area will be in the 20s (especially Thursday night).

◙ Rapid warming trend over the weekend, to near 70° by Sunday.

◙ Highs early next week in the low to mid 70s. Of course, I will adjust temperatures as we get closer.

◙ Temperatures in the 70s will be 20 degrees above normal for this time of year.

◙ This will be a warm Christmas with no snow whatsoever. Maybe next year.

? Return to the top


First Forecast Posted Sunday, December 13

**Tranquil pattern developing this week**
**Freeze late week**
**Unseasonably warm Sunday through Christmas week**
**Rain Christmas week**

◙ No significant weather is expected over the next 7 days.

◙ A cold front will move through North Texas on Wednesday, bringing a few days of below-normal temperatures.

◙ Highs on Thursday/Friday should be in the upper 40s to lower 50s, with overnight low temperatures below freezing (especially Thursday night and Friday night when temperatures may fall into the 20s). The front on Wednesday will not produce any rain.

◙ A warming trend will begin one week from today (next Sunday) and will continue well into Christmas week. I’ve been analyzing the data for the past several days and temperature anomalies between the 19th and 25th look impressive. In fact, temperatures may run 15 to 20 degrees above normal during that period, which would easily place high temperatures in the lower 70s (at least for a couple of days).

◙ A vigorous upper-level disturbance will move into the southwestern U.S. (southern CA/NV/AZ) next Sunday (Dec. 20th) with very strong warm-air advection developing downstream (i.e., over the Southern Plains).

◙ In atmospheric dynamics/physics, warm-air advection is a forcing function for vertical motion which ultimately leads to clouds and precipitation. Therefore, I am forecasting clouds/rain for the first part of Christmas week.

◙ Scattered showers should develop Monday (possibly as early as Sunday night), becoming widespread on Tuesday (the 22nd). I place rain chances on Tuesday the 22nd at 80%.

◙ The strong warm-air advection and deep, northward moisture flux from the Gulf of Mexico should cause the atmospheric precipitable water content to approach the 99th percentile for mid/late-December by Monday night/Tuesday (based on a 65-year PWAT database). It’s quite possible that some of the rainfall during that time period could be heavy. I will be keeping a close eye on the data over the next 8 days.

◙ High temperatures Monday (12/21) through Wednesday (12/23) should be in the upper 60s to lower 70s.

Enjoy the tranquil period for the next 7 days, and the brief cold snap mid/late week.

Have a great week! 🙂

? Return to the top