Marine Weather and Tide Forecast for Holly Hills, CO

SHORT TERM /Through Sunday/
Issued at 151 PM MDT Sat Apr 19 2025

With the upper-level low still to our south, southeasterly flow continues to advect some moisture into the region, with a photogenic deck of stratocumulus across the plains and some bubbling as well over the high country. Cold air aloft within the trough axis will help maintain moderate lapse rates this afternoon in the mountains, where isolated snow showers will occur. These will be much less likely north of I-70 where the upslope (i.e.
southeast) component will be missing, and moisture less pronounced.

Most of the cloud cover will clear out overnight, keeping chilly temperatures in place. The plains will drop into the 20's with perhaps the exception of spots in/around the Denver metro, which may not fall below 30F. The mountain valleys will also be cold given some fresh snow and clearing, falling into the single digits.

As the low pressure ejects east into Kansas Sunday, weak northwest flow will fill in aloft. Highs will warm notably across the lower elevations, climbing into the lower 60's, with the rise being comparatively more muted in the high country where cloud cover will be slightly more persistent during the day.

LONG TERM /Sunday night through Saturday/
Issued at 151 PM MDT Sat Apr 19 2025

A transient upper ridge moves over the Rocky Mountains Sunday night into Monday, but shifts east quickly with westerly flow aloft setting up through Tuesday night. Gusty winds are expected Monday across much of north central and northeast Colorado. The highest wind gusts will be in the mountains Monday. The winds across the plains will be 15 to 30 mph with highs in the low to mid 70s. This leads to elevated fire weather conditions across the eastern plains during the afternoon. Some areas across the plains have fuels that are conducive to carrying fire, while other areas may have started to see the spring green up and are less likely to burn. A fire weather watch may be needed for portions of the eastern plains if model trends continue.

The flow aloft gradually shifts to more southwesterly Wednesday through Saturday. Model differences show up later in the forecast period with the ECMWF digging a deeper trough over the western U.S., while the GFS is more progressive with the pattern.

For north central and northeast Colorado, expect generally warm daytime high temperatures through the upcoming work week. Low level moisture increases by midweek with better chances of late day showers and thunderstorms each afternoon, with snow showers in the mountains. The best chances of showers and thunderstorms across the plains will be Wednesday through Friday.

AVIATION /18Z TAFS through 18Z Sunday/
Issued at 151 PM MDT Sat Apr 19 2025

A deck of stratocumulus with bases current near 030 will continue to expand and persist through mid-afternoon, with some modest lifting of bases to 040-050 anticipated shortly. A return to VFR conditions is expected near 21Z (3pm MT) for all terminals.

Current winds are light and generally from the SE. Direction is expected to hold mostly steady, with a gradual clockwise rotation late afternoon into early evening as winds return to a southerly drainage flow pattern.

VFR conditions will prevail for all terminals on Sun, with development of N/NW winds during the day.

BOU WATCHES/WARNINGS/ADVISORIES
None.