Skip to content

The Next Storm/Next Snow Forecast Discussion from the Cherrywood Observatory – October 12, 2017

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

Forecast Discussion:

If Wednesday was nice weather to you, today will be even better with a warm afternoon in the mid-upper 70's for a high temperature.  And dry. Figure 1 is the surface analysis for Thursday afternoon showing a dry front poised to enter the state (that will cool us a bit on Friday) - the best heating is often seen right before the front arrives with southwest winds and some downslope compression of the air. Friday will be nice and dry, breezy and a bit cooler.

Figure 1: The NCEP Thursday afternoon surface analysis map.

In the Longer Range:

The jet stream buckles over Colorado on Saturday with a sort-of split trough stretching from the eastern Pacific up into Montana.  But there is really very little moisture associated with this. Small troughs (red lines) and ridges (blue lines) are marked in the colored lines across the continent (Figure 2).

Again, from the weather5280.com folks, we have a new product for this column in Figure 3. You can see the rise and fall of daily temperatures for the next 10 days across the top graph. The bottom graph is a vertical stack of 20 GFS computer runs that don't show rainfall until way out around the 19th to 21st. Saturday (purple line) looks dry - but it may be windy.

As a bonus, for Thursday (not the long term) - I've checked in on the HRRR smoke forecast to see if the California fires may darken our skies yet... and though it is forecasted to eventually make it into Colorado, Figure 4 shows it is not here by Thursday.

Figure 2: The GFS 500mb forecast map for Saturday midday.

Figure 3: The 10 day GFS Ensemble forecast (20 runs in the vertical on precipitation) from the GFS for Denver.

Figure 4: The HRRR smoke forecast for midday Thursday.

Current Weather

Mostly sunny

Mostly sunny

75°F

UV Index
3 Moderate
Pressure
29.92 Falling
Visibility
9 miles
Dewpoint
40 °F
Humidity
28%
Wind
E 3.9 mph
Gust
11.1 mph
Wind Chill
75 °F

Hourly Forecast

Today
5 PM
75°F
Mostly sunny
Today
6 PM
72°F
Mostly sunny
Today
7 PM
69°F
Mostly sunny
Today
8 PM
66°F
Intermittent clouds
Today
9 PM
62°F
Mostly cloudy
Today
10 PM
58°F
Mostly cloudy
Today
11 PM
56°F
Mostly cloudy
Tomorrow
12 AM
53°F
Intermittent clouds
Tomorrow
1 AM
51°F
Partly cloudy
Tomorrow
2 AM
48°F
Mostly clear
Tomorrow
3 AM
46°F
Mostly clear
Tomorrow
4 AM
44°F
Clear

7 Day Forecast

Mostly sunny

Wednesday

76 °F

Mostly sunny, pleasant and warmer


Partly cloudy

Wednesday Night

41 °F

Patchy clouds


Mostly cloudy w/ t-storms

Thursday

75 °F

Turning cloudy, warm; breezy, a thunderstorm around in the afternoon


Thunderstorms

Thursday Night

49 °F

A thunderstorm in spots in the evening; otherwise, considerable cloudiness


Showers

Friday

70 °F

Mostly cloudy with a couple of showers


Thunderstorms

Friday Night

46 °F

Cloudy with showers and thunderstorms


Rain

Saturday

50 °F

Chilly with periods of rain


Rain and snow

Saturday Night

39 °F

Cloudy with rain, mixed with a little snow late


Mostly cloudy

Sunday

59 °F

Mostly cloudy with a stray thundershower in the afternoon


Partly cloudy

Sunday Night

36 °F

Partly cloudy


Sunrise and Sunset

Sunrise
6:08 AM
Sunset
7:49 PM

Based on AccuWeather data