Pressure Difference: -0.41 in (Boulder-Eagle)
Granger’s Weather wisdom High winds aloft—if the winds aloft over Denver at 9,000′ or 12,000′ are more than 20 knots, flying on the front range can be hazardous if the inversion breaks and the strong winds descend. Check the wind talkers in the mountainsto confirm. Front Range Pressure Difference.This is the difference in barometric pressure between DIA and Grand Junction . Although there are other factors, the lower the front range pressure troff becomes, the more likely west or tail winds become at our flying areas on the front range. The number will be green if the pressure is higher on the front range. It will turn yellow if there is a slight troff ( neg .5— neg .15 ) and red if there is a strong low pressure troff on the front range ( <.15″ ). You can see this anywhere on Parasoft’ web site on its header.NBR—is a weather station above launch on the ridge. It’s green and good if the winds are NE–SE. Red indicates tailwinds.Shifting winds—You will experience shifting winds before they become catabatic or downslope winds.
Lee trough
A “lee trough” is one and the same thing as a “dynamic trough”. According to the AMS Glossary, it is “A pressure trough formed on the lee side of a mountain range in situations where the wind is blowing with a substantial component across the mountain ridge; often seen on United States weather maps east of the Rocky Mountains and can be formed either as a result of the adiabatic compression of sinking air on the “lee” side of a mountain range, or through cyclogenesis resulting from “the horizontal convergence associated with vertical stretching of air columns passing over the ridge and descending the lee slope.
Can we have the old header back? I miss the pressure difference and winds aloft at first glance…
Niels we can’t use the old Flash header, as it doesn’t work for some mobile devices and the new Wunderground API is more stable than the old parsing technology Parasoft used. The new Wunderground weather widget (see site footer) is an evolving weather widget, and your suggestions will be appreciated.
Niels,
Take a look front rage pressure gradient on the footer of each page.
We are now comparing NBR with western slope airport of Eagle since they are both the same altitude and closer then the last comparison points of DIA and Grand Junction. As we use these new points, I will publish my thoughts about which pressure gradient are significant and which have no effect.
Weather outlook for Saturday 1/1/12
Winds aloft light but Niwot Ridge showing strong westerly gusts at surface. New pressure gradient showing positive +1.4″ but old showing 0. Take some time to get used to new pressure gradient. NOAA weather calling for light snow this PM, up slope flow?