Issue Date: Monday, June 12th, 2017
Issue Time: 10:35A MDT

— Flooding is NOT expected today
— Hail up to 2.5 inches, gusty winds and tornadoes possible in northeast Colorado
— Elevated fire threat for western Colorado

This morning’s surface analysis was an interesting one across Colorado. Near record dew point temperatures were noted in the northeast part of the state – as high as the mid-60s F near the Kansas border with 60F+ dew points even in the Front Range. As the water vapor image shows, below, this is being caused by a strengthening low-level easterly flow in response to an approaching disturbance. As mid-level cooling takes place over Colorado today, expect isolated to scattered thunderstorms across north-central and northeast Colorado. These storms will likely become severe: with very large hail, gusty winds and tornadoes all possible. However, the flood risk will be mitigated by fast storm motions, likely greater than 35 mph. While short-term (30 minutes or less) heavy rainfall will be possible, it will be brief and isolated enough in nature to prevent a flood threat.

Meanwhile, western Colorado continues to stay very dry with Precipitable Water (PWs) well below 0.5 inch, much less in some areas. Although temperatures will be cooler today, low relative humidity values and gusty winds will keep the fire threat elevated today.

Finally, the two snow-melt related high river flows that we have been monitoring (Arkansas River and Cache La Poudre) should begin to slowly subside today as snow melt wanes. Thus, we have removed the Low flood threat for the Arkansas River.

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, Urban Corridor, Front Range:

Mostly sunny early then isolated to scattered thunderstorms developing by mid-afternoon. Max 30-minute rainfall up to 0.7 inches towards the foothills, and up to 1.1 inches farther east. Large hail up to 2.5 inches, gusty winds up to 75mph and tornadoes will all be possible with the strongest cells. However, heavy rainfall is expected to be brief, and a flood threat is not warranted today. Activity will quickly subside by early evening with drier air (temporarily) moving in.

Primetime: 12PM to 6PM

Palmer Ridge, Raton Ridge, Southeast Mountains, Southeast Plains:

Mostly clear early then partly cloudy with an isolated shower or storm is possible during the afternoon hours. Max 30-minute rainfall up to 0.3 inches. Flooding is not expected today.

Primetime: 12PM to 5PM

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

Becoming partly cloudy and cooler today with an isolated shower or storm not out of the question, especially towards the Wyoming border. Max 1-hour rainfall up to 0.3 inches. An elevated fire danger will continue today, with gusty winds, low relative humidity and dry lightning acting in tandem. Stay tuned to local National Weather Service forecasts for more detailed information regarding fire activity.

Issue Date: 6/11/2017
Issue Time: 8:25 AM

A LOW FLOOD THREAT HAS BEEN ISSUED FOR PORTIONS OF THE FRONT RANGE, PALMER RIDGE, URBAN CORRIDOR, AND NORTHEAST PLAINS.
AREA STREAMS WILL CONTINUE TO RUN HIGH AND FAST DUE TO RAPID SNOWMELT.
ELEVATED FIRE DANGER FOR WESTERN AND CENTRAL COLORADO.

Another day of warm and mainly dry conditions is expected statewide, with fire danger being elevated (once again) across western Colorado. With the warm and dry air in place aloft, mostly sunny skies will rule the day. However, moisture is expected to make a return to northeast Colorado behind a cool front (pictured below) as upslope flow returns later this afternoon/evening.

Due to this, isolated thunderstorms cannot be ruled out across the Front Range, Urban Corridor, Northeast Plains, and Palmer Ridge later this afternoon and into the evening hours. It will be difficult for storms to form due to strong capping aloft, but if they do form, they will hold the potential for large hail and strong winds, and periods of heavy rainfall. Thus, a low flood threat has been hoisted. For more details on timing/rain rates, please see the zone-specific forecast discussions below.

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, jump below the map.

Zone-Specific Forecasts

Front Range, Urban Corridor, Palmer Ridge, and Northeast Plains:

Mainly dry and mostly sunny with highs a couple degrees cooler than yesterday’s readings. Moisture will return to the regions by late this afternoon and attempt to fuel isolated showers/thunderstorms during the late afternoon, evening, and nighttime hours. The warm air aloft has created a stout cap that any storm activity must overcome, so nothing more than a low flood threat is warranted. Maximum rain rates will be:

Front Range: 0.8-1.2 inches/hour
Urban Corridor and Palmer Ridge: 1.0-1.5 inches/hour
Northeast Plains: 1.5-2.0 inches/hour

Southeast Plains and Raton Ridge:

Dry and warm underneath mostly sunny skies will be the name of the weather game today. Snowmelt will continue to cause area streams to run high and fast, with the Arkansas River remaining near minor flood stage across the Southeast Plains. High temperatures will be near yesterday’s readings.

Northern Mountains, Central Mountains:

Mainly dry and warm conditions are expected, with high temperatures near yesterday’s readings – perhaps a degree or two cooler. An isolated shower/weak thunderstorm cannot be ruled out for eastern portions of these regions, but chance of occurrence is low (20%). Rain rates from any development won’t pose a flood threat, as maximum rates will be 0.15-0.3 inches/hour.

Timing: 3 PM – 9 PM

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

Mostly sunny and warm again today, with high temperatures near yesterday’s readings. Breezy/gusty winds will keep fire weather concerns elevated, with Red Flag Warnings issued for a large portion of western Colorado. Please visit your local NWS office website for more details.

Issue Date: Saturday, June 10th, 2017
Issue Time: 9:32 AM MDT

A LOW FLOOD THREAT CONTINUES FOR MINOR FLOODING ALONG THE ARKANSAS RIVER NEAR LA JUNTA.
ELEVATED FIRE DANGER FOR WESTERN COLORADO.

There isn’t much to say about today’s weather forecast other than it is going to be dry and hot across Colorado. As you can see from this morning’s soundings from Denver (top) and Grand Junction (bottom), dry air is in place from the surface all the way into the upper-levels of the atmosphere. The main weather concern today will be the breezy winds across western Colorado, where Red Flag Warnings have been issued by the National Weather Service. Be careful with any activities that may start a fire, as conditions are favorable for rapid fire growth. As far as flooding is concerned, minor flooding will continue along the Arkansas River near La Junta due to rapid snowmelt, and numerous other streams will flow a bit higher and faster due to the same conditions.

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, jump below the map.

Zone-Specific Forecasts:

Urban Corridor, Palmer Ridge, Northeast Plains, Southeast Plains, and Raton Ridge:

Dry and hot conditions will be the name of the game today, with high temperatures pushing a few degrees warmer than yesterday’s readings. As far as cloud cover is concerned, mostly sunny skies are expected throughout the day, with mostly clear skies overnight and into tomorrow morning.

Front Range, Southeast Mountains, Northern Mountains, Central Mountains, San Juan Mountains, and San Luis Valley:

Mostly sunny, hot, and dry conditions are expected today. Breezy conditions are expected, especially for northern portions of the state. Today’s a good day for a hike, just be sure to bring plenty of water with you and stay hydrated.

Northwest Slope, Grand Valley, and Southwest Slope:

Red Flag Warnings have been issued for counties in each of these regions, as breezy conditions combine with the dry and hot weather to elevate fire concerns. The conditions will be favorable for rapid fire growth, so please be careful.

Issue Date: Friday, June 9th, 2017
Issue Time: 10:05AM MDT

— Minor flooding will continue on Arkansas River near La Junta through at least Saturday
— Elevated fire danger for central and western Colorado

This morning, instead of showing water vapor imagery, shown below is the Denver atmospheric sounding from 6AM. Although the surface dew point temperature was still 51F, note the pronounced drying just above the surface. This will quickly mix down to the surface across nearly the entire state, with the exception of far eastern and southeastern areas where stubborn moisture will keep a slight chance of a weak shower/storm in the forecast.

The main headline today will be the combination of gusty winds, warm temperatures and very low relative humidity for central and western Colorado. An elevated fire danger will increase this afternoon.

Finally, minor flooding is currently occurring on the Arkansas River near La Junta. This will continue through the day, and a Low flood threat is posted here. Stay tuned to the Pueblo National Weather Service for updates.

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:

Southeast Plains:

Mostly sunny early then a few clouds with an isolated shower or storm possible for far southeast areas. Max 1-hour rainfall up to 0.25 inches. Precipitation related flooding is not expected. A Low flood threat is posted for the Arkansas River near La Junta for minor flooding.

Front Range, Urban Corridor, Palmer Ridge, Raton Ridge, Southeast Mountains, Northeast Plains:

Mostly clear and much warmer today with gusty winds. There will be an elevated fire threat across the foothills and higher elevations. Several creeks in the Front Range have elevated flows, but are expected to stay below Minor flood stage. Flooding is NOT expected today.

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

Mostly sunny and continued warm today with gusty winds developing later in the afternoon. An elevated fire danger will develop during the afternoon. Stay tuned to local National Weather Service forecasts for more detailed information.