Grand Junction(KKCO)-The shortwave troughs that enhanced Monday’s showers have pushed east and carried drier air into the area, especially over north east Utah and central and northwest Colorado. Surface dew points remain in the upper 40’s to lower 50’s across the forecast. The north west flow around the ridge over the great basin will advect this drier air into the area which, along with a mid-level subsidence inversion, will produce a downturn in showers and thunderstorms today. Also, today should be as much as 10 degrees warmer than Monday from abundant sunshine.
Wednesday will see another significant upturn in wet thunderstorms across the area. Another strong surge of subtropical moisture will be carried into the area by flow around a high over New Mexico and a trough lifting over the area from the southwest. The chance of rain increases across all of western Colorado and eastern Utah Wednesday afternoon and night.
A couple of moisture surges in the mid to long term forecast. The first is forecast for Thursday. An upper level trough will also skirt the northern portion of the forecast area and add upper level dynamics will increase the chance of rain slightly Thursday afternoon and evening. A ridge axis builds back overhead by the end of the week but is very transitory. Skies clear and precipitation chances decrease late in the week.
The ridge axis slides to the east by mid weekend allowing the moisture to once again push northward. A pacific low moves inland over the pacific northwest coast Sunday. The low moves to the east an over the northern Rockies late Monday into Tuesday. We will get an increase in showers and thunderstorms as the southwesterly flow aloft continues to bring moisture overhead. Southern part of the trough and the disturbances rotation around southern edge of the trough will add dynamics for the formation of precipitation.