Monday, October 13, 2008

Colder Weather

After a cold and wet weekend the upper level low is still in place over the dessert SW but will be moving out quickly to the NE. As it moves east tropical moisture will move northward and bring cloudiness tomorrow afternoon to the Front Range area. This will clear out by Wednesday mid-day and bring a nice remaining part of the week. We will continue to have cold mornings near freezing for the next few days.

Tuesday, October 7, 2008

Changing weather this weekend

An upper level system is forecasted to dig into southern California Saturday morning. On Sunday morning the upper level Low is expected to eject out of the Great Basin and into the Central Rockies with a 100kt jet max over Colorado. This will provide great upper level support for enhanced moisture convergence in the lower levels on Sunday. A shallow ridge will build in wake of this dynamic trough towards the end of next week.

Saturday mid-day mid level moisture will be transported in the low level jet from the south and increase throughout the day. SW flow will dominate the Colorado region as the upper level system tracks NE on Sunday. Drier NW flow will return to CO by late Monday as the system travels into Canada.

The remaining part of this week will be fairly nice and then a major change for the weekend. A lee-side Low will form on the eastern plains as the main system makes it's way into Colorado Saturday morning. SE flow will dominate the surface levels bringing abundant moisture up from the Gulf late Saturday, producing rain showers across the Central Rockies. Surface moisture convergence will be the strongest Saturday night and into Sunday morning. Cold front passage looks to be early Sunday morning along with rain showers. Precip ending by Sunday night and clearing out by Monday morning. Winds will be gusty around 15-20 kts before and during frontal passage.

Temperatures with this system will be colder but not likely for snow in the Denver area. There is a chance that some rain/snow mix might be present on Sunday morning but temperatures still warm enough keeping it in a rain form. After the system totally ejects out the a High pressure moves in, subsidence with cold air will be in place for a few days beginning next week. Lows Monday and Tuesday will be hovering around freezing and slow to warm through the week.