NWS FWD Area Forecast Discussion at 115 PM CDT Sat Apr 20 2024

838 FXUS64 KFWD 201815 AFDFWD Area Forecast Discussion National Weather Service Fort Worth TX 115 PM CDT Sat Apr 20 2024 ...New Short Term, Aviation... .SHORT TERM... /NEW/ /This afternoon through Sunday/ Waves of rain and storms have continued over North Texas today as strong isentropic lift prevails behind the cold front and brings elevated parcels to their level of free convection. Temperatures have already reached their highs today, with near steady or falling temps in the 50s are expected this afternoon. Now that the cold front has pushed through the entire CWA, surface based instability is shunted to our south, but an axis of modest elevated instability/MUCAPE still exists south of I-20. This will provide the fuel for another round of storms starting early this afternoon over the western zones and progressing eastward into the evening hours for the remainder of the region. This round of convection is in response to forcing from an upper level disturbance as it moves across. The evidence of this disturbance is confirmed by the batch of storms currently organizing across the Big Country. PoPs are near 100 percent for all of North Texas this afternoon and/or this evening. Additional rainfall amounts of 1-2 inches are expected with this activity. Isolated (10% of the area) will have storm totals of 3-4 inches. While the rain will be widespread, and occasionally heavy, we think the pace and rain rates will be spaced out enough to avoid flash flooding issues, thus no flood watch will be issued. Still minor flooding of low-lying and flood prone locations is a concern. The severe weather threat is non-zero, but is highest south of I-20, better still in Central Texas, where hail up to quarter size is a threat. Rain will end/clear the region from NW to SE this evening and overnight. Clouds will be more stubborn, but eventually drier air in the low levels will work to erode them Sunday afternoon. Temperatures will be seasonably cool in the upper 40s and low 50s for lows tonight, while highs will only reach the low to mid 60s. TR.92 - And now a personal note, this is my last forecast shift. I've worked at this office just shy of 20 years as both a forecaster and the Science and Operations Officer. I have enjoyed serving the people of our region, hopefully bringing a little more predictability to our chaotic atmosphere and teaching others some meteorology along the way. I am moving on to a new opportunity behind the front lines of operational forecasting at the regional office where I will help advance the NWS in what will likely be a period of unprecedented change brought about by artificial intelligence being used for traditional weather forecasting purposes. I'm in awe where numerical modeling is today compared to the start of my career 25 years ago. Where we'll be in 10 years is probably going to be even more incredible. Before you get too excited about having that perfect forecast of a rain shower down to the minute, I want to use this AFD for my last "Ted talk" to explain why we're hitting a wall in the quest to create that perfect accurate forecast, and why those lame jokes about meteorologists getting paid to be wrong aren't going to go away anytime soon. The atmosphere is a nonlinear system, meaning that our ability to forecast it is extremely sensitive to knowing the exact condition of every single breath of air. We crudely sample the atmosphere directly with instruments that aren't precise or numerous enough, and make even more approximations with remote sensing like satellites. And while computing power will no longer become the bottleneck in forecast information (AI represents an order of magnitude leap of cheap computing power for weather  prediction purposes!), the technology and ability to know the initial state of the atmosphere will continue to hold forecast accuracy back. So while we may never get the perfectly accurate hyper-detailed computer model, we are now getting something very valuable...the probabilities of different outcomes based on the guesstimates of what the current state of the atmosphere may look like. In other words, if weather prediction were a game of Blackjack, we learned the rules of the game in the 20th century (discovery of meteorology as a science), figured out the best ways to play a hand to win during the last few decades (numerical modeling), and now we are entering the phase where we're able to  count cards and know our exact odds with every move (probabilistic forecasting). Notice that even counting cards in a game of Blackjack with a computer means we don't know the outcome of every single hand. There's still the element of random chance at play (or in the weather business we call that chaos theory). But over many hands (or forecasts), we'll be able to make better decisions knowing those probabilities. The role of the meteorologist of the future will become one that communicates the probability outcomes that are important to the people they serve. Some of the kinds of forecasts I think we'll have in 10 years are the chance of: a strong tornado hitting your city in 6 hours, a nearby river flooding your house next week, a record cold snap or heat wave in 2 weeks, and so on. Monitoring and communicating these kind of probability predictions will help prepare society to be ready for whatever Mother Nature throws at us. Take note young weather enthusiasts...don't get into this field just because you think weather is interesting, make weather a career if you're passionate about helping people prepare for the worst of it! TR.92 && .LONG TERM... /Issued 246 AM CDT Sat Apr 20 2024/ /Sunday Night Onward/ A surface ridge will build southward from the Plains into North and Central Texas on Sunday as a weak mid level ridge develops aloft. This will set the stage for a cool and dry start to next week, with below-normal temperatures expected both Sunday and Monday. Sunday night should be the coolest night as a good radiative cooling scenario allows temperatures to fall into the lower and mid 40s. Conditions will remain dry while becoming slightly warmer Monday and Monday night, though temperatures will still be 5 to 10 degrees below normal. A general warming trend will continue through the midweek period as the mid level ridge strengthens overhead. A shortwave rounding the northeast periphery of the ridge will push a cold front southward towards the Red River late Tuesday, beginning a period of unsettled weather mid to late next week. The front will likely stall somewhere between the Red River and the I-20 corridor, providing a focus for isolated showers and storms Tuesday night and Wednesday. POPs will initially be low, however, as subsidence from the ridge works against convective development, and will keep rain chances in the slight chance range. The ridge will begin to break down on Thursday as the next shortwave trough approaches from the west, bringing somewhat better chances for rain Thursday into Friday. Convection may initiate along the dryline as it enters the Big Country, and we may need to monitor the potential for a few severe storms late Thursday into Friday. As the shortwave exits to the east, a larger scale upper trough will be entering the Rockies and will provide even better rain chances as it emerges in the Plains. There may be a lull in precipitation late Friday into next Saturday, but convection will redevelop by late next Saturday into next Sunday as the upper trough approaches and storms develop along an attendant Pacific front. A few severe storms may again be in play, which is typical for April, and we will know a lot more the further into next week we get. 30 && .AVIATION... /NEW/ /18z TAFs/ Waves of showers and thunderstorms continue to develop and track across the Metroplex TAF sites. After this current batch moves through the TAF sites through 18z, the amount of instability for thunder will be somewhat limited, so expect showers to dominate but have VCTS to cover the occasional lightning strike. However, stronger upper level lift will arrive late this afternoon, likely yielding another round of storms on station between 22z and 00z. This wave will wind down with a widespread shield of rain and occasional rumbles of thunder this evening -- with all convective activity finally clearing the Metroplex from NW to SE around 3z. In the meantime IFR to MVFR CIGs will prevail, and visibility outside of precipitation should range around 5-7SM. IFR CIGs should persist overnight, with gradual lifting to MVFR expected Sunday morning as drier air moves in. N/NE winds at 10-15kt will persist through the period. For Waco, similar trends, expect the convective window will mainly be between 0z and 5z. TR.92 && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth   58  50  66  48  72 / 100  90   5   0   0 Waco               64  50  63  45  69 /  90 100   0   0   0 Paris              57  48  64  42  70 / 100  90   5   0   0 Denton             57  46  64  42  71 / 100  80   5   0   0 McKinney           55  49  64  44  71 / 100  90   5   0   0 Dallas             57  50  65  47  73 / 100 100   5   0   0 Terrell            57  49  63  44  71 / 100 100   5   0   0 Corsicana          60  50  65  46  70 /  90 100   5   0   0 Temple             65  49  63  45  70 /  80 100   0   0   0 Mineral Wells      58  46  65  44  72 / 100  80   5   0   0 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$