Manuel Nears Hurricane Strength In Southern GoC

TS Manuel has intensified to near hurricane strength over the southern GoC this afternoon. The NHC now forecasts a slow motion to the north and has issued hurricane warnings (see above) for part of the east coast of the Gulf. The 1 pm MST visible image below shows a large but distinct eye with the storm. The fact that Manuel is intensifying and staying over the GoC complicates the low-level moisture situation.  Right now the pressure gradient is down-the-Gulf toward the storm, which will take dry air further south.

However, there is an up-the-Gulf pressure gradient at the north end - above is surface plot at about 1:30 pm - as the short wave at 500 mb moves across the Great Basin. There is a battle among very dry, dry, and very moist air masses underway. It is likely that low-level moisture will increase across southeastern Arizona during the rest of the week. But, the warm air suppression at middle-levels continues very strong, with 500 mb temperatures today just below zero - ugh. The 12 UTC WRF forecasts have backed off on the convective forecasts for today and tomorrow, keeping storms to the east of Pima County. Still need to keep a wary eye on Manuel and the high moisture over the GoC.