Tuesday, June 12, 2018

Tropical Development in Gulf Not Likely...

Like they did with Alberto, NHC has designated a tropical wave over the West Central Caribbean as Invest 91L that allows them to begin running computer models of the system.  Of course, as we saw with Alberto early on, without a definite initialization point, model tracks are not very good before anything forms.  NHC believes in the next 2-3 days development will be hindered by an upper trough that is creating way too much wind shear.  However, they feel during days 4-5 shear may be less allowing for possible organization over the extreme SW Gulf.   They have greatly reduced the area of possible development indicating to me that they feel nothing will develop.  Regardless, a surge of tropical moisture will be heading northward into Texas (where rain is much needed) & western Louisiana for Sunday & Monday.   David used a great graphic showing this moisture surge on his early programs & will probably show it again at 9 PM.    It’s way too soon to know if the rain shield will include us, although we’ll be on the “wet side” of whatever forms or not.  Going to the beaches this weekend should be OK as it’ll be wetter the farther west one goes from NOLA.  


Today was a fairly classic summer-like afternoon as storms bubbled up during daytime heating.   Slow movement allowed for some 2-3” rainfall amounts in spotty areas and more of the same is likely the next 2-3 days.    I was watching some of the morning & noon weathercasts with the rain chances at “50%”.   Do most of you know what that means?  Frankly I don’t and never used 50% since that would make me look like I didn’t know any better than a coin flip.   I preferred to use “ below normal” rain chances (20-30%), “near normal”  (40-60%) and “above normal” (above 60%).  One could also substitute Less Likely, Likely or more likely instead of using the percent  chances.   The confusion comes since probabilities have NOTHING to do with time.   An 80% chance DOES NOT mean it will rain 80% of the time.  The forecast verifies if it only rains for 5 minutes.  I liked to use the example of dividing SE LA/MS into 100 equal squares.  20% chance means 20 squares would/might see rain while 80 would not.   80% chance means 80 squares would see rain while 20 would not.  It’s just a better visual for me.  Bottom line, will it rain tomorrow?  My answer in the summer….SOMEWHERE!   Stay tuned!

No comments: