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061 FXUS65 KBOU 041728 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1128 AM MDT Sat Jul 4 2026 .KEY MESSAGES... - Scattered strong to severe storms expected this afternoon and evening, with large hail and gusty winds the main hazards. - Considerable improvements to fire weather conditions today, but dry thunderstorms will be possible for the higher elevations that will keep elevated concerns in place today. - A few storms expected each day of the coming week, with the highest probabilities shaping up for Tuesday and Wednesday from the Front Range eastward. && .DISCUSSION /Through Friday/... Issued at 143 AM MDT Sat Jul 4 2026 Another night of nocturnal convection has brought heavy rainfall and flash flooding to areas across the eastern plains, once again. Areas of southeastern Washington County and northeastern Lincoln County received up to 5 inches of rainfall as very slow moving storms passed over. Storms have now moved out of the area and the Severe Thunderstorm Watch has been cancelled. All flash flood concerns have now diminished and all warnings have been allowed to expire. Today will bring another threat of severe weather across much of the forecast area, where the SPC has a Slight Risk (2/5 threat level) for all areas along and east of I-25, and a Marginal Risk (1/5 threat level) for the Front Range Foothills. Tonight`s nocturnal storms have done a good job of keeping low level moisture in place, with dewpoints remaining in the mid to upper 50s all the way west to the I-25 corridor as of 330AM. With temperatures expected to warm efficiently through the morning, and MLCAPE increasing to upwards of 2,000 J/kg through the afternoon mixed with enough 0-6km bulk shear for supercell formation, storms will likely develop along the foothills by 2PM, and move eastward across the plains through 9PM. While strong to severe storms will be possible along the I-25 corridor, it looks like the more robust environment will be farther east on the plains where the better moisture is anticipated to coincide with the higher MLCAPE values. Expect hail up to two inches in diameter and winds around 60 mph with the stronger storms. With the better moisture expected across the plains, there will be an elevated threat for dry lightning across the higher elevations today that will keep elevated fire weather concerns in place in these areas, but fire weather concerns for low relative humidity and gusty winds will see significant improvements. Ridging is expected to start rebuilding over the Rockies on Sunday that will warm temperatures up by a few degrees over today`s upper 80s to low 90s. Winds are expected to be lighter under the ridging for at least the first half of the week while 500mb winds are fairly lax. This will keep critical fire weather concerns minimal, with only localized elevated conditions expected through midweek. Temperatures are expected to reach the 90s across the plains each day this week, with potential to see temperatures climb into the triple digits by next weekend. Afternoon convection will be possible on Sunday and Monday, with only light precipitation expected, mainly for areas along the Palmer Divide. By Tuesday, ensembles show an increase in PWAT values that will bring a return to scattered to numerous afternoon showers. 500 mb flow starts to increase again on Wednesday that will increase bulk shear to around 25 to 35kts, allowing for potential of a few stronger to severe storms developing in the afternoon. It will also bring increased fire weather concerns back to the higher elevations by the second half of the week. && .AVIATION /18Z TAFS through 18Z Sunday/... Issued at 1125 AM MDT Sat Jul 4 2026 VFR conditions expected to prevail for all terminals through the TAF period. Some weakening of the current southerly flow is anticipated in the coming hours, before isolated high-based convection starts to initiate and drift east into the I-25 corridor early afternoon. Latest guidance indicates more questionable moisture availability for thunderstorms this afternoon at the terminals, though even elevated SHRA would be capable of producing robust outflow gusts of 35-40 kts. Thus, will maintain the PROB30 groups for now. As the afternoon and early evening progresses, east and southeast flow should take hold as convection becomes more widespread over the plains. Some potential for gusts to persist into the early evening, particularly if we see numerous developing east to west outflows. Expect a return to drainage during the evening with clearing skies, and lighter/more VRB winds prevailing Sun AM. Smoke coverage is somewhat less this morning, and smoke production from ongoing fires is expected to continue to trend downwards as fire activity moderates. As such, anticipating a gradual reduction in the potential for slant range visibility impacts tonight and particularly for Sunday. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...9 AVIATION...BRQ