Monsoon preview this weekend

Tomer’s Take:

• A surge of pre-Monsoon season moisture hits Colorado Saturday-Monday. Normal Monsoon season runs July-August.
• The areas most affected are the Western Slope and Southern Mountains of Colorado.
• Precipitable water increases to 200% of June 30-year average values.
• Bottom line: plan on smaller weather windows. Expect mountain thunderstorms by 10am or earlier across the Western Slope and Southern Mountains. And, overnight/morning rain is possible in the San Juan’s on Sunday morning and possibly Monday morning.

Colorado state climatologist Dr. Russ Schumacher says it’s a robust moisture surge by June standards:

quite the change in moisture upcoming in western Colorado…precipitable water (amount of water vapor in the atmosphere) at Grand Junction goes from near-record low today to near-record high for mid-June by the weekend. Finally some rain on the way for the western slope! #cowx pic.twitter.com/KSys7xaWU9

— Russ Schumacher (@russ_schumacher) June 15, 2022

Precipitable water % of normal on Sunday morning 6/19.

Hourly forecast for 13-14ers in the Central San Juan Mountains. Notice the rain and thunder chances (and south winds).