Week of August 6 – 12
The 4th of this year’s 15 predicted named storms formed in the Atlantic, while Tropical Depression 5 (not yet a storm) formed in the Gulf. Storms can play a vital role in boosting late wet-season rain totals, especially in year’s where June and July rainfall totals are not bountiful.
The District received a total of around 16 inches in June and July, chiming in about a half inch above the 10-year combined average for those two months. Miami-Dade received 22 inches over the same period, whereas the Southwest Coast (Naples-Ft Myers) only received 14 inches, which deceptively appears to be close to the District-wide average, but is actually around 6 inches below the SW Coast’s 10-year combined average for June and July, and more reminiscent of the Lake Okeechobee’s 12 inch two-month total (which happens to be around normal for the Lake). High July rainfall totals (9-10 inches) in the Kissimmee Basin was good news for the Lake, and helped make up for the below par 5-6 inches of June rainfall in the Kissimmee. Currently, August is off to a slow start — with a District-wide average of around 2 inches through the first third of the month.
In any event, the storm season ratcheting up is a sign that higher rainfall events may be on the horizon depending on where the storms turn.
Lake Okeechobee: Lake O ,Kissimmee. Last week averaged around 1,000 cfs being discharged out of Lake Toho. Further downstream, 500 cfs discharged out of Lake Kissimmee through S65 into the Kissimmee River and under 100 cfs discharged out of Lake Istokpoga. Lake Okeechobee averaged around 2,900 cfs of inflows last week, with around a third of that inflow entering from the Kissimmee River through the S65E. Fisheating Creek is the only unregulated surficial discharge into the Lake. It averaged 280 cfs last week.
Lake stage is hovering at around 9.4 ft msl, about the same level as last week. That puts current Lake stage at around 2.5 ft below mid August of last year, about 2.1 ft below mid August of drought year 2001, and over 6 ft below mid August of 2005, which was the highest mid-August lake level since August of 1995, when Lake O’s level also topped 16 ft msl.
Everglades: Everglades National Park ,WCA3,WCA12. Regulatory stage in Loxahatchee has been tracking right along the 5-yr average since the start of June, which incidently coincides with last year’s June through mid-August rise. Slough water depths in the central slough (Sites 1-7 and 1-9) are around 1 ft deep. That places the wetting front up in the ridge landscape community.
Regulatory stage in WCA2 had been tracking about a half foot below its 5-yr average since the start of June, but has made up that deficit in August. Its stage currently coincides with the 5-yr mid-August average. Slough water depth in its center (Site 2-17) is around 0.75 ft deep, also placing the wetting front in the ridge landscape type. There are currently no discharges through the S10s or S11s. Around 4 ft of water is pooling up behind the S10s, and around 3.5 ft of water is pooling up behind the S11s.
Regulatory stage in WCA3A continues to stay down, currently around 1.5 ft below its 5-yr average for mid August, and about 0.6 ft below mid August of last year. This year’s mid-August regulatory stage for 3A is lowest its been since the drought year’s of 1989 and 1990. Its a full 2.5 ft lower than the record mid-August high-water mark set in 2005, the result of record setting June rainfalls in 2005. Slough water depth in southern 3A is 1.75* ft deep, in comparison to a 0.25 ft slough depth north of I75 at Site 63.
The S12s remain mostly shut. The S12A averaged 7 cfs last week, but all the other gates are closed. The S333, sending water towards NE Shark River Slough, averaged 100 cfs for the week. Mid August flows were also low last year for the S12s, averaging under 500 cfs for the month, in comparison to an average August flow for the S12s being closer to 2,000 cfs over the past 5 years. Water depth in central Shark River Slough at P33 is currently tracking at its 5-yr mid August low-water mark, at about a 1.3 ft depth, which is about a half foot below the mid August 5-yr average. Flows into Taylor Slough headwaters via the S332s were also a near zero average for the week. Water depths downstream in Taylor Slough at P37 are just under a foot deep.
Big Cypress: Big Cypress National Preserve ,Corkscrew and OK Slough . Preserve-wide stage has momentarily dropped a few inches below this years late July high-water-mark to date. That place’s current preserve-wide water depths in the preserve around 4 inches below the mid-August average, and around 7 inches below our annual average high-water mark, which typically occurs in September. Water depths in the southern half of the preserve, south of US41, remain around a half foot deeper than north of I75. After a late start, water levels finally appear to be rising near the surface in Okaloacoochee Slough, but they are still down 1-2 ft lower than the rest of the preserve.