Tropical storm Gustav discussion number  11
NWS TPC/National Hurricane Center Miami Fl.   Al072008
500 P.m. EDT Wed Aug. 27 2008
The latest air force reconnaissance mission into Gustav indicates that the cyclone has weakened a bit with a minimum pressure of 999 mb and a peak SFMR wind of about 45 kt.  The initial intensity is lowered to 45 kt for this advisory.  Despite the short-term weakening…Atmospheric and oceanic conditions appear favorable for re-intensification once Gustav moves away from Hispaniola…Likely tonight.  Still…There remains some disagreement among the intensity models with the GFDL and HWRF models showing robust strengthening…And the statistically-based ships and LGEM models that forecast only modest strengthening.  Given the uncertainty…The official forecast essentially splits the difference and is very similar to the previous advisory.
Gustav continues to crawl west-northwest ward with an initial motion of 300/03.  The overall forecast philosophy remains unchanged. Dynamical models show a middle to upper-level ridge extending from the gulf of Mexico eastward over Florida and into the western Atlantic.  This pattern should result in a westward to west-northwest ward motion over the next couple of days with a gradual increase in forward speed.  In 2-3 days…The ridge is forecast to weaken and this should result in a gradual turn toward the northwest…Taking Gustav over or very near western Cuba and into the gulf of Mexico.  By day 5…Some of the global models are now suggesting that the steering currents could weaken resulting in a slowing of the forward speed.  In general…The track models have not changed significantly since the last advisory and the new official forecast track is very similar to the previous one.
It is important to note that there still remains significant uncertainty regarding Gustav’s ultimate track at days 3-5…And it is much too soon to know what impact this system may have on the northern gulf coast.

Forecaster Rhome/Pasch