Years With NO JUN TCs and 1 or 2 JUL systems--what happened

[USAwx1]

With two prospective systems in the ATL at this time, Lets look at years which had NO JUN system and either one or two JUL systems and see what the rest of those seasons did for us in order to draw conclusions as to what the rest of the current season might hold.

It should be noted of course that IF neither of these systems reach TS status this research wont mean squat—although with the POTENTIAL there I thought it would be interesting to examine the what ifs while were waiting for more developments with the two invests.

Below are years with NO JUL systems and ONE JUN system:

1955, 1961, 1963, 1969, 1971, 1976, 1978, 1980, 1998.

Statistics for 1955:
NS: 12, H: 9, IH: 6

Statistics for 1961:
NS: 11, H: 8, IH: 7

Statistics for 1963:
NS: 9, H: 7, IH: 3

Statistics for 1969:
NS: 18, H: 12, IH: 5

Statistics for 1971:
NS: 13, H: 6, IH: 2

Statistics for 1976:
NS: 10, H: 6, IH: 2

Statistics for 1978:
NS: 12, H: 5, IH: 2

Statistics for 1980:
NS: 11, H: 9, IH: 2

Statistics for 1998:
NS: 14, H: 10, IH: 3

The average number of NS in the years above was 12; the average number of hurricanes was 10, and intense hurricanes 3. For landfall data on the years 1955-1980 See the link below:

http://millenniumweather.com/tropical/yh.html

Information on the 1998 season is available via UNISYS at:

http://www.weather.unisys.com/hurricane ... index.html

ENSO and QBO in the years w/ NO JUN systems and ONE JUL system—How does it compare with the Current (Neutral/West QBO)

1955: LA NINA / West QBO
1961: ENSO Neutral / West QBO
1963: Neutral to La Nina / E to W QBO
1969: Neutral to El Nino / West QBO
1971: La Nina / West QBO
1976: Neutral to El Nino / W to E QBO
1978: ENSO Neutral / West QBO
1980: ENSO Neutral / West QBO
1998: La Nina / East QBO

It would appear to me that there is a VERY STRONG correlation between a west QBO and Seasons with No June systems and only one July system. 5/9 seasons had a W QBO throughout. The correlation between a stormless JUN and one system in JUL and the ENSO appear weaker since there were several years which were transitional between ENSO phases, several Neutral and others La Nina or El Nino throughout.

Years w/ NO June systems and 2 JUL systems:

There were only three seasons since 1948. Those being: 1970, 1973, and 1985.

Statistics for 1970:
NS: 10, H: 5, IH: 2

Statistics for 1973:
NS: 8, H: 4, IH: 1

Statistics for 1985:
NS: 10, H: 5, IH: 2

The average of all three years ended up being, 9 NS, 5 H and 2 IH. For Landfall data see link below:

http://millenniumweather.com/tropical/yh.html

ENSO and QBO correlation:

1970: La Nina / East QBO
1973: La Nina / West QBO
1985: ENSO Neutral / West QBO

There really arent enough years here to be able to extract any reliable correlations between seasons with No June storms and two July systems.

According to the comparison between the mean number of season w/ No June storms in comparison to those with one and two July systems, those hoping for an active season will want to hope that only ONE of the current Invests develop before the end of the month.

If we look at the Following AUG and SEP of those years w/ No JUN storms and ONE JUL system (combined AUG/SEP total) we find that the “lid” did come off and in a big way—especially in 1969, 1971, and 1998.

1955: 9
1961: 6
1963: 6
1969: 11
1971: 10
1976: 8
1978: 7
1980: 7
1998: 10
Mean: 8

As far as the years w/ no June Storms and two JUL systems, the result was MUCH LESS impressive than those w/ one storm in JUL.

1970: 5
1973: 4
1985: 6
Mean: 5

[cycloneye]

That is an excellent research that is a complete one about late starts of seasons.

[USAwx1]

Thanks. But unless those two Invests develop, this research won't mean beans. We've already been over the season w/ NO JUN or JUL systems--and those years (in the means) ended up having average activity.

never hurts to look at and discuss your options.

[senorpepr]

Wow--- what an interesting find?! Great research, as always.

[HurricaneBill]

It's kinda weird how 1969 was an El Nino year, yet the Atlantic had 13 named storms and 5 unnamed storms.

[bahamaswx]

Nice research, as always.

[USAwx1]

It's kinda weird how 1969 was an El Nino year, yet the Atlantic had 13 named storms and 5 unnamed storms.

The Answer to that MAY be three fold. The PDO was in the negative phase, which enhances Atlantic Activity (mitigates EPAC activity). The QBO was west. and The ATC was in the strong cycle.

[Brent]

Fascinating.

[USAwx1]

It's kinda weird how 1969 was an El Nino year, yet the Atlantic had 13 named storms and 5 unnamed storms.

It should also be noted that 2002 was VERY similar.