565 FXUS65 KPUB 300529 AFDPUB Area Forecast Discussion National Weather Service Pueblo CO 1129 PM MDT Thu Aug 29 2019 .SHORT TERM...(This evening through Friday) Issued at 330 PM MDT Thu Aug 29 2019 ...Front moving through this evening bringing an uptick in thunderstorms for Friday... Quite hot out there this afternoon with KCOS having broken the old record high. They hit 95 degrees breaking the old record of 93 set in 1962. KPUB is still several degrees from the old record (102 set in 1970) and appears may stay just shy. KALS is also a little shy of their old record (87 set in 2013) but may tie or break it in the next hour or two. Meanwhile, two areas of convergence are focusing convection this afternoon. One is along the front across eastern sections of the area which may generate some isolated thunderstorms across Kiowa county in the next couple hours. Second area is along surface trof axis across eastern Las Animas/western Baca counties where, in spite of dew points falling off into the lower 40s, sufficient elevated CAPE has fueled a couple strong storms over the last hour. In general, thunderstorms will be confined to the mountains and along these two focus features through the evening, but will be high based and mainly lightning and wind makers. Could be some brief rainfall or even some brief small hail with the stronger storms across the southeast plains this evening but the hail threat is rapidly diminishing as dew points continue to mix out. Cold front will accelerate down the Palmer Divide late this afternoon and evening in the wake of shortwave translating across northeast CO into NE/KS. Frontal passage at KPUB is expected around 5 PM...and will make its way through the remainder of the southeast plains this evening through the overnight hours. Low clouds will develop behind the front Friday morning which may briefly spread into eastern El Paso and Pueblo counties during the morning before eroding eastward again by afternoon. Upslope flow and increased moisture for Friday will set the stage for a potential day 2 severe thunderstorm event. However, timing of the disturbances through the upper ridge appears to come through during the overnight/early morning hours. There is another shortwave and associated upper jet which will glance through northern Colorado Friday afternoon and evening but the majority of the forcing appears to stay to the north. This may mean that forcing for thunderstorms across southern CO will be primarily driven by differential heating and upslope which could be why high res models appear are rather scant with thunderstorm coverage for Friday. Best forcing will be across northern areas (i.e. Pikes Peak region). With the potential for CAPE up to 2000 J/kg and deep layer shears around 30-35 kts...one or two severe thunderstorms will be possible across the eastern slopes of the southeast mountains and adjacent plains, particularly the Palmer Divide and Raton Ridges. Large hail and damaging winds will be the primary storm threats. For now think the stronger storms will be more isolated in coverage given the aforementioned reasons. -KT .LONG TERM...(Friday night through Thursday) Issued at 330 PM MDT Thu Aug 29 2019 Friday night-Sunday...Weak to moderate northwest flow aloft across the region Friday night becomes generally light and variable later Saturday and into Sunday, as upper level high pressure across the Desert SW and Four Corners builds into the Rockies. Latest models are not as clear cut with convection across the far southeast plains Friday night, though with scattered storms over and near the higher terrain pushing east out across the I-25 Corridor Friday afternoon, can't rule out convective outflows helping to trigger storms further east. Storms across the I-25 Corridor and southeast plains Friday night could be strong to severe, with the potential for at least quarter size hail and damaging winds. Again, depending on how convective fires Friday night, may be dealing with low clouds across the plains early Saturday morning, possibly as far west as the I-25 Corridor. For Saturday and Sunday, with modest moisture in place, will continue to see isolated to scattered afternoon showers and storms over and near the higher terrain both days, though with warming aloft under the building high and weak flow aloft, coverage of daily storms looks to decrease through the weekend. The warming aloft will also allow for highs to warm back to well above seasonal levels once again by Sunday. Monday-Thursday...The upper high over the Central Rockies on Monday is progged to slowly slide south and east of the area through the middle of next week, leading to slowly increasing available moisture across the region once again. With that said, Monday looks to be a mainly dry and hot day, though can't rule out some high based afternoon storms over the higher terrain, especially along and west of the ContDvd. With available moisture slowly increasing from west to east into the middle of next week, as well as a weak backdoor front looking to move across the Plains on Tuesday, there should be increasing coverage of diurnal showers and storms across the region through the middle of next week, along with a gradual cooling trend back to near to slightly above seasonal levels. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 1124 PM MDT Thu Aug 29 2019 Forecast models show the potential for low stratus at or near KCOS and KPUB toward morning and thru Fri morning. However, at this time there is uncertainty as to whether there will just be scattered low clouds or a broken to overcast layer, and for now will just put a scattered layer in the forecast for these sites. There will be the possibility of showers/tstms in the vicinity of KCOS mainly after 20Z on Friday. KPUB may also see showers/tstms in the vicinity Fri evening. KALS is expected to have VFR conditions && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...KT LONG TERM...MW AVIATION...28