Skip to content
Join our Newsletter
Join our Newsletter

Next Storm/Next Snow Forecast Discussion from the Cherrywood Observatory – May 5, 2019

This content was originally published by the Longmont Observer and is licensed under a Creative Commons license.

In Brief:

Nearly perfect weather continues through Monday midday. Drop mic.

A cold front and deep upper air trough move in Monday afternoon and a long period starting with thunderstorms continuing with rain and nighttime snow at times runs Tuesday through next Monday and beyond.

Forecast Discussion:

High pressure (with some clouds) continues today. The ridge will build a bit more overhead - so temperatures will warm a touch more. West winds at the surface will warm things a bit to the upper 70'sF.

The Longer Range Forecast:

With the next trough coming in just a bit sooner, and with clouds increasing, we will probably only see the lower 70'sF on Monday. The front should slide down the front range increasing our chances of rain and thunderstorms around sunset (big blue line Figure 2). We probably won't see severe thunderstorms along I-25 and westward, but we may see a marginal or slight risk out on the eastern plains. I'll update you on that as we get closer.

A quick check on the GFS 10-day total water has us in, what is probably, a down slope notch again, but we do get 1 to 1.25 inches of water. The bullseyes of heaver precipitation are staying consistent to our west and east (Figure 3). The GFS has no Longmont snow but the GEM (Figure 4) does give us 1-2 inches (or a touch more) snow over the next 10 days. If anything accumulates, it should 'wash' away in the daytime rain and temperatures that follow.

Figure 1: The forecast surface map for Friday PM from NCEP.
Figure 2: the graphical forecast for the next 10 days for Longmont, CO from
Figure 3: the forecast accumulated precipitation map from the GFS and for Colorado,over the next 10 days.
Figure 4: the forecast accumulated snow map from the GEM and for Colorado, through the next 10 days.


Mostly cloudy

Mostly cloudy


UV Index
0 Low
30.07 Steady
10 miles
45 °F
N 0 mph
6.5 mph
Wind Chill
65 °F


Partly sunny w/ t-storms


89 °F

Very warm with sun followed by some clouds; a shower or thunderstorm in spots late this afternoon

Partly cloudy w/ t-storms

Tuesday Night

57 °F

A shower or thunderstorm in spots early this evening; otherwise, partly cloudy and mild

Partly sunny w/ t-storms


89 °F

Periods of clouds and sunshine with a shower or thunderstorm in spots late in the afternoon

Partly cloudy

Wednesday Night

55 °F

Partly cloudy

Partly sunny


90 °F

Very warm with sun and some clouds

Mostly clear

Thursday Night

55 °F

Clear to partly cloudy

Mostly cloudy


89 °F

Rather cloudy and very warm; breezy in the afternoon

Mostly cloudy

Friday Night

60 °F

Mostly cloudy and mild

Partly sunny


91 °F

Breezy in the morning; otherwise, partly sunny and very warm

Partly cloudy

Saturday Night

53 °F

Breezy in the evening; otherwise, partly cloudy

Sunrise and Sunset

11:32 AM
2:25 AM

Based on AccuWeather data