826 FXUS64 KFWD 211720 AAC AFDFWD Area Forecast Discussion...UPDATED National Weather Service Fort Worth TX 1220 PM CDT Wed Mar 21 2018 .AVIATION... /18Z TAFs/ VFR conditions will prevail but strong and gusty winds are expected on Thursday. South winds between 5-10 kts will occur through tonight. The winds will become more southerly late Thursday morning and increase to 15-20 kts with gusts of 20-25 kts through the afternoon hours. JLDunn && .SHORT TERM... /Issued 337 AM CDT Wed Mar 21 2018/ /Today and tonight/ Pacific moisture arcing around the top of an upper ridge over the Desert Southwest is resulting in occasional cirrus across North and Central Texas. At the surface, a ridge axis has begun to shift east of the region, which will is resulting in a switch-over to southeast winds. Wind speeds will be fairly light today, but may increase to 10-15 MPH across the western third of the region this afternoon as the gradient begins to tighten. Otherwise, a pleasant day is in store with high temperatures in the upper 60s to lower and mid 70s. Increasing dewpoints and southeast winds should keep tonight's low temperatures a tad warmer than the past few nights. 30 && .LONG TERM... /Issued 337 AM CDT Wed Mar 21 2018/ /Thursday through Tuesday/ The warmup will continue Thursday into Friday as the Plains are dominated by mid and upper level ridging. With the center of surface high pressure shifting farther to the east, southerly winds will begin to increase during the day Thursday and this trend will continue into Friday. Highs on Thursday should top out in the mid to upper 70s with further warming into the 80s on Friday. We'll be centered just to the east of the ridge axis during this time which will keep northwest flow aloft overhead and little to no chance for precipitation. As we head into late Friday and Saturday the upper ridge will begin to slide east of the region as a large upper trough digs into the western U.S. As it does, surface pressures will fall in the Plains, tightening the pressure gradient across North Texas and allowing southerly winds to really increase. This will also help pull some better Gulf moisture northward. By Saturday, a large surface cyclone will be moving into the Midwest states dragging a cold front southward into the Plains. We'll have ample moisture across North Texas, but we should remain strongly capped for much of the day as the front approaches the Red River. Thanks to westerly winds above the surface, 850 mb temps will warm considerably during this time and we should see highs climb into the mid and upper 80s despite an increase in cloud cover. Saturday night looks like it will mark the beginning of an active period of weather across North Texas with a couple of shots of severe storms followed by a more significant threat of heavy rainfall through next week. As the aforementioned front lifts northward Saturday night, the nose of a 110 kt upper jet will spread into southwest Oklahoma resulting in a broad area of diffluence aloft over the region. Stronger height falls spread into west Texas during this time and low level warm advection begins to ramp up. We could see some elevated showers and thunderstorms develop mainly north of I-20 into Oklahoma during this time. This initial impulse will move northeast of the region early Sunday although flow aloft will continue to strengthen as the upper trough continues to dig over the southwestern U.S. We should see a good dryline surge eastward by Sunday afternoon into our western counties. With an upper pattern favorable for weak embedded perturbations to provide sufficient forcing for ascent to overcome weakened capping along and east of the dryline, scattered thunderstorms are expected into the evening hours, mainly west of I-35. Steep mid level lapse rates and modest deep layer bulk shear will support severe thunderstorms with a hail/wind threat. Convection should diminish in coverage later in the night. We should see a similar setup again on Monday afternoon, with another eastward dryline push and the potential for scattered severe storms mainly across the west and northwest counties. We will begin to transition from a severe threat to more of a heavy rainfall threat beginning late Monday night into Tuesday. This is when the large upper trough begins to close off over the southwest U.S. Meanwhile, a cold front will slide southward into the Southern Plains Monday night, likely reinvigorating earlier convection across parts of North Texas. This trend continues into Tuesday and Wednesday. While forecast confidence typically diminishes beyond 5-7 days, the model signal for heavy rainfall is quite strong and is reflected as well in numerous GFS/ECMWF ensemble perturbations. The upper pattern definitely has the classic features of a heavy rainfall event with a slow moving upper low, strong persistent upper diffluence over North Texas, surging precipitable water values, and surface frontal features to concentrate low level convergence. We'll continue to monitor this over the next several days. Dunn && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 73 51 77 60 80 / 0 0 0 0 5 Waco 73 48 78 58 81 / 0 0 0 0 5 Paris 67 45 73 55 73 / 0 0 0 0 10 Denton 71 48 77 58 79 / 0 0 0 0 5 McKinney 69 47 75 57 77 / 0 0 0 0 5 Dallas 72 51 78 60 80 / 0 0 0 0 5 Terrell 70 47 76 57 78 / 0 0 0 0 5 Corsicana 71 48 76 58 78 / 0 0 0 0 5 Temple 74 49 77 58 81 / 0 0 0 0 5 Mineral Wells 73 49 78 58 85 / 0 0 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ 82/24