FTB 05-30-2016: Strong storms possible in the east, but pleasant elsewhere

Issue Date: Monday, May 30, 2016
Issue Time: 10:20AM MDT

— A Low flood threat has been issued for the Northeast Plains, Palmer Ridge and Southeast Plains

This morning’s weather map is a bit busier than past days. As the water vapor image below shows, yesterday’s transient ridge is a thing of the past. Today, it is replaced by an elongated, but broken trough stretching from the Canadian border south-southwest into the Baja of California. A closer inspection reveals this trough is actually comprised of two different centers of action: a main one from about Utah northward and a secondary one in the form of a weak cut-off low in southwest Arizona. Several days ago, it appeared these two features would move as one and could provide for a widespread rain across CO. This is no longer the case. Instead, the northern feature will propagate rather swiftly eastward, while the southern feature will more-or-less lose touch with steering winds and may not move much.


The northern feature is the main player today. It will trek eastward accompanied by a surface low centered over western South Dakota and a weak cold front stretching into Colorado’s Northeast Plains. With precipitable water values between 0.8 and 1.0 inch expected in the region by this afternoon,this will be the focal point for a few stronger thunderstorms capable of heavy rainfall, hail up to 1.5 inches and perhaps a tornado along the Kansas border. A Low flood threat has been issued for eastern areas.

For everyone else, expect a similar day to Sunday with isolated to scattered showers and thunderstorms from early afternoon into the evening hours. Just like yesterday, the bigger impact of this action will be gusty winds as a dry lower-atmosphere will help evaporate most of the rainfall before it reaches the ground.

Today’s Flood Threat Map

For more information on today’s flood threat, see the map below (hover over threat areas for more details). For Zone-Specific forecasts, scroll below the map.
Zone-Specific Forecasts:

Northeast Plains, Southeast Plains, Palmer Divide:

Mostly sunny early with scattered thunderstorms developing by early afternoon and lasting into the early evening hours. A few of the strongest storms will be capable of produce heavy, short-term rainfall, hail up to 1.5 inches and wind gusts up to 60mph. An isolated tornado is also possible. Max 1 hour rainfall rates up to 1.7 inches will lead to isolated field and road flooding. A Low flood threat has been posted.

Primetime: 1pm to 8pm

Front Range, Urban Corridor, Raton Ridge:

Sunny early with isolated to scattered showers and a weak thunderstorm developing by early afternoon and lasting into the early evening hours. Hourly rainfall rates up to 0.4 inches are possible, along with gusty winds up to 45 mph. Flooding is not expected.

Primetime: 12pm to 7pm

Central Mountains, Northern Mountains, Southeast Mountains, San Juan Mountains, San Luis Valley, Grand Valley, Northwest Slope, Southwest Slope:

Mostly sunny early then turning partly cloudy. Isolated showers and perhaps a weak thunderstorm are possible mainly over the higher terrain. Max hourly rain rates up to 0.25 inches. Gusty winds up to 50 mph will be possible under the thunderstorm updrafts. Flooding is not expected today.