Yesterday was mild and cloudy, but then I believe it cleared up for observations in the evening.
This morning has been sunny, hot and still.
The NWS in Boulder, CO, forecasts a mostly sunny day, with a 20% chance of showers and thunderstorms, and a high temperature of 94 F. The winds will be from the northeast at 6-9 mph. This evening will be partly cloudy, with a 20% chance of showers and thunderstorms, and a low temperature of 64 F. The winds will be from the northeast at 5-9 mph, becoming light and variable by midnight.
The NWS in Boulder, CO, has issued a Hazardous Weather Outlook concerning isolated storms this afternoon. Primary threats will be gusty winds (up to 40 mph), small hail and heavy rains.
The visible satellite image shows a few cumulus clouds forming over the tops of the Front Range. These may become some afternoon thunderstorms.
The 12 Z upper air sounding from Boulder shows a relatively damp atmosphere, though no saturated layers are present. There was 0.74 inches of precipitable water present in the column. There was 16 J/kg of Convective Available Potential Energy (CAPE) and -772 J/kg of Convective Inhibition (CINH). The Lifted Condensation Level (LCL) was 897 m. There was a moderate thermal inversion near the surface, and the 0-3 km average lapse rate was 4.7 C/km.
The hodograph shows that there was 10 kts low-level shear (due mostly to directional changes) and 17 kts deep-layer shear (due mostly to speed changes).
The surface observations (from the SPC Mesoscale Analysis Map) show warm temperatures and moderate humidity, based on the dewpoints. The skies are clear, and the winds are generally southerly, statewide.
The surface pressure chart shows that there are no strong pressure systems or gradients over Colorado this morning. The RAP shows that the pressure will drop with diurnal heating, but no strong pressure gradients are expected over Colorado.
The NAM 250 mb chart shows northeasterly flow aloft over the state today. Winds are circling around a high pressure system over the CO/UT border.
The HRRR simulated reflectivity shows that a few storms are expected to fire by 22 Z, all over the Front Range. However, these storms are expected to track southwest with slow storm motions due to the circulation around the high pressure ridge.
The HRRR predicts that the high temperatures for Boulder will peak in the mid 90’s by 23 Z.
The HRRR shows that the winds in the Denver area will remain light. This image has been excluded from today’s post.
The NAM shows cloudy skies into our observation window, perhaps clearing in time for the late shift.
The HRRR shows fewer clouds, making observations possible for the early shift, but then likely for the middle and late shifts.
Today will be a warm, but pleasant day. I bet the participants will be able to make observations tonight. The early shift will be dicey, but I am tending towards the HRRR’s output on cloud cover.
Thank you for reading my post.
The forecasts from the National Weather Service are from The NWS Homepage
The upper air soundings and mesoscale analysis plots are from the Storm Prediction Center website.
The satellite data, model data, and forecasted soundings are from College of DuPage – SATRAD