wxgeek's weather-Good monsoon flow coming-Update July 5

Update Thu Jul 5

The North American Monsoon is now in full swing. Upper ridge currently located over MO will bring a nice flow of moisture from the GUlf of Mexico across northern Mexico and then northward into AZ, NM, UT and CO. Radiosone soundings across the region indicate Precipitable Water values now between 1 inch and 1.5 inches, so the atmosphere has ample moisture to develop storms. Atmpspheric stability is also now marginally unstable which will support active thunderstorm development. Surface dew point temps across the CO plains now in the mid to upper 50's which is a good indication that the monsoon has begun.

For today (Thu) best precip chances will be over eastern UT and western CO, with some showers and thunderstorms possible across the foothills as monsoon moisture plume favors these areas to our west. On Friday, moisture plume is expected to move farther east bringing very good precip chances to the High Country, foothills and plains of CO. Models indicate up to an inch of precip is possible on Friday across the foothills and Urban Corridor. A weak cold front is expected to move through eastern CO late Thu night and set up a northeast upslope flow on Friday, which will help usher in additional low level moisture and provide nice lift to develop storms along the foothills by Friday afternoon. Some storms may be very heavy Friday afternoon and evening and could produce localized flash flooding, especially in recent burn areas where mud flows could develop. Small to medium hail is also possible along with frequent lightning. Storms may persist late into the night on Friday.

For the upcoming weekend, the upper ridge over MO is expected to begin rebuilding to the west, so it will be moving across CO this weekend and is forecast to re-establish over northern UT next week. At the surface, a weak upslope flow is expected on Saturday which will keep temps 10-20 degrees below where they have been, and even below seasonal norms. With upslope flow in place, more showers and thunderstorms are expected to develop Saturday afternoon and evening, especially along the foothills and adjacent Plains. On Sunday, surface flow becomes more southeasterly which will allow temps to warm back to near seasonal norms. More showers and thunderstorms will be possible Sunday afternoon and evening.

Update July 5

For next week, upper ridge will be located west of CO, so flow aloft will be northerly. This flow does not transport monsoon moisture into CO, so precip chances will diminish, but there will still be mid level moisture available that will allow for isolated afternoon and evening showers and thunderstorms to develop, mostly over the higher terrain, but some storms may drift over the foothills and adjacent Plains. Any precip will be on the lighter side as compared to this week and weekend however. Temps will also warm back above seasonal averages next week. The extreme heat now over the midwest and east will move with the upper ridge to the western U.S. next week.

As for smoke, surface flow today is more southerly so smoke should be a little better. On Friday and Saturday, surface flow will be from the north, so smoke from WY and MT fires will drift back over CO. On Sunday, surface flow more southerly, so less smoke from these fires. Next week, flow aloft will be from the north, but surface flow should be more southerly. This translates to smoke plumes at higher altitudes moving south across CO, but nighttime smoke at lower levels will drift northward.
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"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

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Current models indicate that a moist monsoon flow will bring very good chances for precip the remainder of this week and this weekend. Flow aloft around upper high over the lower MS valley will bring air from the Gulf of Mexico into NM and up into CO. Showers and thunderstorms will increase in coverage and intensity this week, leading to good chances for precip over most areas. Some concern for recent burn areas having flash flood events with heavy mud and debris flows possible, but for most areas this moisture will be very welcome. Some heavy storms will be possible, so flash flooding will be possible along with hail and lightning.

Models indicate monsoon flow will be with us through early next week, then upper high forecast to move more into NM/AZ which would limit strong monsoon flow.
_________________
"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

Bump for July 5 update