Keeping eye on Gustav

Gustav has been an interesting tropical system. It has defied intensity forecasts pretty much its entire lifespan. When data suggested it should become a hurricane, it remained a tropical storm of mediocre intensity. Then yesterday, indications were that it could perhaps intensify quickly, but not to the amount that it eventually did. This afternoon, its sustained winds were up to 150 mph, making it a very strong Category 4 (out of 5) hurricane. It just passed over the western portion of Cuba, which probably caused it to weaken just a little bit. However, it's moving back into a very favorable environment to at least sustain itself, if not become a little stronger.

Naturally, everybody is wondering about how it will impact New Orleans. Computer model and official forecast tracks indicate that the center may make landfall west of the city. However, that is not necessarily good news. The strongest part of a hurricane is the right-front quadrant; the image at left illustrates where that sector is with Hurricane Gustav. Essentially, you put an imaginary plus-sign over the hurricane, with the line that's normally drawn up-down located along the path that the system is moving. In the right-front quadrant, you're in the area where you're adding the effects of the winds moving "forward" (since tropical systems spin counter-clockwise) to the effect of the system simply moving forward.

Gustav will have an impact on our weather in the second half of the upcoming week. At this time, it looks like some of the tropical moisture from Gustav will be siphoned northward and used by the cold front that should be passing through sometime on Wednesday or Thursday. We'll be fine-tuning the rain chances in the forecast as the Gustav situation becomes more clear.