Earlier this week, I mentioned that the current stretch of silence in the tropical Atlantic was approaching a record for the current decade (2000-2009). Well, nothing has developed in the recent days, as expected, so the current stretch of 12 days without so much as a tropical depression is the longest September stretch of the current decade.
Today, I decided to further expand upon this brief research and see how the current quiet compares to the past 30 years (1980-2009). In this slightly more involved research, I looked at the number of consecutive days without a tropical cyclone (depression, storm, or hurricane) during the month of September as well as the period from August 15 – October 15 , which roughly covers the most active portion of the hurricane season (see image below). These dates were the limits of any consecutive stretch. In other words, if there were no storms from August 10-20, it was counted as 6 days (Aug 15-20).
Number of storms per 100 years for the Atlantic basin.
I intended to go back to 1970, but data about storms – specifically, tropical depressions – were missing in some instances prior to 1980. Thus, for the sake of consistency, I used the 30-year period from 1980-2009. In terms of consecutive days without a cyclone in September, here’s what I found:
| Year | Days w/o Cyclone | Dates of Quiet Stretch |
| 1992 | 16 | 9/1-9/16 |
| 1991 | 16 | 15-30 |
| 2009 | 12 | 13-24 |
| 1986 | 12 | 19-30 |
| 2008 | 10 | 15-24 |
| 1997 | 10 | 21-30 |
| 1994 | 9 | 9/12-9/20 |
| 1983 | 9 | 9/1-9/9 |
| 1996 | 8 | 16-23 |
| 1999 | 7 | 24-30 |
d
The dates listed in the third column represent the first and last day without a cyclone or the beginning or end of the period (9/1 and 9/30). All dates are within the month of September.
At present, the current stretch is in a tie for the 3rd longest during the month. The maximum number of consecutive days that can be achieved is 18 (9/13-9/30). If this were to occur, it would be the most consecutive days without a cyclone in the month of September during the last 30 years. Right now, the NHC is monitoring an area of showers and thunderstorms over the Atlantic that could develop in the next 24 hours. After that, conditions will not be conducive to strengthening according to their discussion. Of course, we’ll be sure to monitor the situation over the weekend as it pertains to this record stretch of calm.
When expanding the time frame to Aug 15 – Oct 15, the current stretch doesn’t look so impressive.
| Year | Days w/o Cyclone | Dates of Quiet Stretch |
| 1991 | 30 | 9/15-10/14 |
| 1986 | 27 | 9/19-10/15 |
| 1997 | 19 | 8/15-9/2 |
| 1992 | 19 | 8/29-9/16 |
| 1994 | 15 | 10/1-10/15 |
| 1983 | 15 | 10/1-10/15 |
| 2002 | 14 | 8/15-8/28 |
| 1993 | 14 | 10/2-10/15 |
| 2006 | 13 | 10/3-10/15 |
| 1982 | 13 | twice |
| 2009 | 12 | 9/13-9/24 |
| 1987 | 12 | 9/27-10/8 |
d
Right now, the present stretch sits in a tie for the 11th longest in the last 30 years – certainly nothing to write home (or blog on the interwebs) about. Of course, if the present stretch were to last a few more days, it would move into 5th place on the list above. And what do those top 4 years have in common? You know it… El Nino.
Weather Talk 