Post from a former co-worker and in NWS. Very knowledgeable.
The NHEMI total TC activity is well below normal season-to-date
(thru 8/12). 18 named storms so far (normal is 24 season-to-date),
6 hurricanes/typhoons (normal is 12), and 2 major hurricanes/typhoons
(normal is 6). Total ACE is only 52% of normal season-to-date.
Yes, the Atlantic has been active, but only in some ways. Basically,
Hurricane Beryl is the only anomaly so far and accounts for almost all
the high numbers for the Atlantic season-to-date (named storm days,
hurricane days, major hurricane days, and ACE). Not saying Beryl
was not a major anomaly, but one storm does not reflect the
entire season or season-to-date in the larger climatology
picture.
For instance, take the most active Atlantic hurricane season overall,
2005. Through 8/12 that season, we already had 8 named storms,
4 hurricanes, and 2 major hurricanes (one strong Cat 4 and a Cat 5).
This blows away (no pun intended!) the 2024 season-to-date. Since
we have the warmest Atlantic ocean temps on record (~60 yr reliable
record period), and conditions in the atmosphere are said to be so
favorable, where is this hyperactivity for TCs in the Atlantic?? 2005
was a true hyperactive season, not only total, but it started early and
never stopped, w/ active named storms most days July-Oct.
Now, it is still early overall, but a couple things on that. 1) All
forecasts are going for 20+ named storms in the Atlantic this
season, and two have 25+ w/ one 33 and 2), none of the global
models shows any tropical storm or hurricane development in
the Atlantic the next 10 days, which brings us to 8/22. We have
5 named storms so far. Although 15 more named storms after
8/22 has happened before, and will get us to 20 for the season,
20 or more named storms for the true hyperactive forecasts
(25+), that's going to be tough. Not saying it can't happen, but
the Atlantic only has so much room and it actually can get too
"crowded" w/ storms at times (happened in 2023 and other years).
TCs need room around them to develop and esp. to get intense,
otherwise, they will inhibit each other's full potential. So even
though you can have 4 named storms at once, that tends to be the
limit based on past very active seasons. And even in the most
active seasons, there are cycles where conditions overall wane at
times for TC development in the entire Atlantic, so it can't be full
throttle to the max all the time in a season (2005 and a few other
seasons going back to 1851 are close).
The eastern Pacific is among its slowest, if not slowest start since
reliable satellite records began (1970). 2024 already broke the
record for the latest first named storm in this basin, and Carlotta
was the second latest first hurricane on record in this basin (record
is Aug 24 set in 2003). The western Pacific is not doing much better
w/ ACE only 33% of normal season-to date.