Area Forecast Discussion
Issued by NWS Wichita, KS
Issued by NWS Wichita, KS
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351 FXUS63 KICT 301954 AFDICT Area Forecast Discussion National Weather Service Wichita KS 254 PM CDT Tue Apr 30 2024 .KEY MESSAGES... - Late afternoon evening storms possible along and especially east of I-135. Severe storms likely with any storm that develops along the front. - Evening storms may add to the ongoing flooding issues from the Flint Hills into southeast KS. - Additional storms likely on Wed with severe storms again possible, especially west of I-135. && .DISCUSSION... Issued at 254 PM CDT Tue Apr 30 2024 Water vapor imagery currently shows some shortwave energy lifting across Eastern Nebraska with the main upper trough still back over the Northern Intermountain. At the surface, Pacific front/dryline extends from eastern Nebraska to near KSLN and just northwest of KHUT. Front/dryline will continue tracking east this afternoon and by 21z is expected to extend generally along or just west of I-135. Storms are expected to develop along the boundary generally in the 20-23z time frame. Confidence on the more widespread activity is still higher further north, closer to the better upper dynamics and further away from weak high rises. However, almost all of the CAMs are developing storms in our forecast area, which makes sense given the extreme instability and minimal capping. With an abundance of instability and modest deep layer shear, still looking for supercells with large hail and damaging winds possible. Can`t rule out a brief tornado, given the presence of decent 0-3km CAPE and a sharp boundary, especially if a storm can remain anchored on it for a period of time. As the storms track off to the east this evening, they will be moving into an area that has already seen extreme rainfall the last several days, so flooding would become more likely. So the current flood watch looks on track. Low level jet will increase as the evening hours progress which will impinge on the front as it starts to lay out more east- west. This should lead to continued storm development and potential back-building which may lead to additional flooding, especially over the Flint Hills along and south of Highway 400. Starting to feel more confident that showers and storms will linger across at least south central and southeast KS throughout much of Wed morning as 850-700mb moisture transport persists. In addition, a tight 700mb baroclinic zone will move through during the morning hours which should help showers and storms continue. With CAPE above 850mb in the 1,000-2,000J/KG range, some large hail will remain possible with any of the storms Wed morning. The main question will be if and how many storms develop on the dryline/triple point Wed afternoon/early evening. The model trends have been to push the warm front/dryline further to the southwest with the triple point now expected to be between Pratt and Dodge City where yesterday at this time it looked like it would be west of Great Bend. With the better upper forcing still back to the west and northwest, current thinking is that we will not get numerous storms to develop along it with just a few storms likely. All severe hazards will be possible with any storm that develops along the dryline late Wed afternoon/early evening and will track off the east. So for surfaced based convection Wed, feel areas west of I-135 will have the best chance, generally after 22z as storms move-in from the west. Another round of elevated storms will be possible Wed evening/night as the better upper forcing moves out of the Rockies and into the High Plains. Locations along and north of I-70 will have the best chance to see this activity. Storm chances will remain over the area on Thursday as the front moves back through the forecast area with southeast KS having the only chance for storms on Thu night. By 12z Fri, the upper low will be lifting across the Upper Mississippi Valley with westerly mid and upper flow across the Plains. Meanwhile, the surface boundary is expected to stretch from southern MO into southeast OK, which is where the better storm chances will also be located. We should see a break in storm activity during the day Fri with additional development Fri night as a fast moving impulse slides across Nebraska, which will push another cold front through the forecast area. Storms are expected to be moving off to the east Sat morning with most of Sat dry. However, both ECMWF and GFS still agree on lifting a southern stream impulse out of the Desert Southwest and across the Southern Plains for late Sat night into Sun which may bring a round of showers and storms to mainly southern KS on Sun. && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 1249 PM CDT Tue Apr 30 2024 A number of aviation concerns are expected over the next 24 hours. SCT to BKN MVFR cigs are slowly moving eastward across south- central Kansas early this afternoon, but shouldn`t affect TAF sites from here on out. VFR conditions should prevail at most TAF sites until about 22Z. A weak frontal boundary/dry line sliding across the area, and a pronounced wind shift from southerly to northwest/westerly. Sustained winds are generally around 15 to 20 knots with gusts up to 30 to 35 knots on both sides of the boundary. By 22Z, thunderstorm development is anticipated along the boundary, and a line of broken strong to severe storms will gradually slide eastward through the late afternoon and evening hours along and east of the Kansas Turnpike. The main concerns will be very large hail, damaging wind gusts, and perhaps a tornado or two. These storms may impact KICT, but it`s difficult to go with more than a PROB30 at this time given coverage may be isolated. Storms are expected to continue moving eastward tonight, and KCNU may also be impacted later tonight. Additional thunderstorm development is expected during the nighttime hours into Wednesday morning, but this activity is not expected to be severe. However, frequent lightning and heavy rainfall may accompany these storms Wednesday morning. && .ICT WATCHES/WARNINGS/ADVISORIES... Flood Watch from 8 PM CDT this evening through Wednesday morning for KSZ069>072-093>096-098>100. && $$ DISCUSSION...RBL AVIATION...JC