Dr. Klotzbach 2009 Season August 4th Update

[clfenwi]

The CSU team is now 1/3 on their 15 day forecasts. Fred, with an ACE of 10 was the only storm to form during the forecast period. That, of course,is well in line with the forecast of below average ACE (~37% of the climatological norm).

Forecast for the September 20-Oct 4 period comes out today. I suspect that they will go with a below average forecast again, given the lack of current activity, nothing in the models, and the lack of a favorable MJO phase.

[cycloneye]

Forecast from September 20 thru October 4=Below Average

Another below average forecast.

Below is an excerpt from the forecast.

Forecast
We believe that the next fifteen days will be characterized by activity at below-average levels (less than 70 percent of climatology). This is due to a combination of factors including the fact that there are currently no active tropical cyclones in the Atlantic basin. Most of the global models hint at weak, if any, development over the next five days. The MJO is currently in a somewhat unfavorable mode for Atlantic tropical cyclone formation (Phase 4), and both the Global Forecast System (GFS) ensemble and the statistical model forecasts predict that the MJO will likely remain in an unfavorable mode for most of the forecast period. Average activity for the September 20 – October 4 period over the years from 1950-2000, and the forecast for 2009 are displayed in Table 3.
Figure 3 displays the tracks that tropical cyclones have taken during the period from September 20 – October 4 for the years from 1950-2008. Figure 4 displays the September 20 – October 4 forecast period with respect to climatology. The September 20 – October 4 period is still fairly active from a climatological perspective, although somewhat less active than the previous 15-day period.

http://hurricane.atmos.colostate.edu/In ... 4_2009.pdf

[cycloneye]

Forecast from October 7 thru 21

Below average again.

http://hurricane.atmos.colostate.edu/In ... 6_2009.pdf

[Macrocane]

Grace is out of the previous and the new forecast periods, how will they take it into account?