Sabin Elementary School, CO Hourly Weather Updates

Key Messages

• Flash flooding and a few severe storms will be the main threats through this evening, as another round of storms moves east- northeast across the forecast area.
• Monsoon moisture lasts through the weekend, bringing scattered showers and thunderstorms each day with locally heavy rain and a severe weather threat.
• Warming and drying trend still set to begin Monday.
• Another active day possible middle of next week.

Discussion

/Through Friday/... Issued at 111 PM MDT Fri Aug 14 2026

Our main concern late this afternoon and evening will be another round of strong thunderstorms, capable of producing flash flooding and severe weather. Nearly full sunshine over the plains has allowed the airmass to destabilize through early this afternoon. Low level moisture was rather impressive with dewpoints holding in the lower to mid 60s east of the I-25 Corridor. That`s pushing MLCAPE values into the 1000-2000 J/kg range per latest SPC analysis. While bulk shear is marginal (only around 25 kts) for organized severe storms, we have sufficient instability to drive large hail and damaging wet microbursts from stronger storms. While there was some drying noted in the 700-600 mb layer on the most recent ACARS soundings, we still expect efficient rain producers given low level moisture and updraft intensity, and enough to warrant a Flood Watch for flash flooding in areas that saw recent heavy rains - see HYDROLOGY section below for more details.

Like most convective episodes, there will probably be some weaker convection that lingers behind the initial stronger storms that push east across the plains. Otherwise look for gradual clearing overnight, but patchy fog/stratus development once again with a very moist boundary layer.

On Saturday, deep layer shear increases as flow aloft strengthens from the west-southwest. At the same time, we`ll still have a fair amount of low/mid level moisture present, which means growing instability and another round of afternoon and evening storms. Some of these may be severe again due to increased shear but a little decrease in instability as some slight drying is still forecast.

Sunday is shaping up to be another active weather day, and potentially even higher than Saturday as persistent low level easterly flow and moisture advection occurs over the plains. A failure mode would be too much moisture/low level cloudiness over the plains, but at the same time that could mean even greater instability and more favorable shear profiles if we get enough heating to break the cap.

We`re still on course for drier weather Monday and Tuesday as the ridge axis retrogrades slightly. That allows for a drier west- northwest flow aloft and warm advection. High temperatures will likely (>70% chance) return to 90F+ by Tuesday.

Wednesday should feature higher chances of storms again (30-50% chance), as another front is scheduled to bring slight cooling but moistening late Tuesday into Wednesday. We don`t see much change in the overall pattern through the end of next week, which at this point favors fairly normal Colorado weather with near normal temperatures and isolated to scattered afternoon and evening storms each day.

Aviation

/00Z TAFS through 00Z Sunday/... Issued at 530 PM MDT Fri Aug 14 2026

Showers and thunderstorms are ongoing at all terminals and will likely continue for the next few hours before gradually shifting east this evening. Due to higher confidence of convection lingering, have upgraded the PROB30 to a TEMPO though 03Z, with a PROB30 from 03Z to 05Z. Lightning and VRB outflow winds up to 30 kts are likely with any storm. Some uncertainty with winds behind the storms this evening, but guidance does favor light and variable winds before a light drainage flow replaces it. Low stratus down to 500 feet is possible with the light and variable winds, so have introduced it to the TAF. Will continue to monitor to see if it develops overnight.

Similar set-up is expected for tomorrow, with convection beginning 20Z-21Z. Heavy rain reducing visibilities, lightning and gusty outflow winds will be the main concerns. However, guidance is in more agreement of showers/storms ending by 01/02Z rather than lingering into the evening like today.

Watches / Warnings / Advisories

/WARNINGS/ADVISORIES... Flood Watch until 10 PM MDT this evening for COZ036-041-042- 044>049.