textproduct: Miami - South Florida

KEY MESSAGES

Updated at 1225 AM EDT Fri Oct 17 2025

- Gusty northeasterly winds will result in dangerous rip currents at all east coast beaches today. This risk will persist into much of the upcoming weekend as winds remain elevated along the coast.

- The combination of onshore winds and the approaching new moon in the lunar cycle will result in continued minor flooding along the east coast of South Florida within 1.5 to 2 hours of high tide.

- Marine conditions will remain hazardous across the Atlantic waters today as northeasterly swell continues to interact with the Gulfstream current. Cautionary conditions will continue in Biscayne Bay and our local Gulf waters.

SHORT TERM

(Today through Saturday) Issued at 1225 AM EDT Fri Oct 17 2025

The passage of a weak frontal boundary to the south of our region over the last several hours has resulted in an enhancement of a pressure gradient and consequently an increase in surface wind speeds over our local waters and the immediate east coast. For the remainder of the region, nocturnal stratification has resulted in the decoupling of winds inland resulting in calm conditions with a light northeasterly breeze persisting from time to time. ACARS (aircraft data) from SoFlo airports as well as tonight's 00z MFL upper air sounding continue to depict quite the dry atmosphere from 800mb up with a copious amount of mid-level dry air present. The 1.24 inch precipitable water value observed on the 00z MFL sounding remains below the 25% percentile of historical precipitable water for this time of year. A shallow layer of moisture remains from the surface up to 800mb which may still support the potential of quick moving vertically-capped isolated showers from time to time, mainly along the immediate east coast of the region during the first half of today. Based on current radar trends via KAMX, have bumped up rain chances along the east coast of South Florida to 15-20% over the next couple of hours. Rain chances across the region will remain less than 10% this afternoon as instability remains meager and drier mid-level air mixes down to the surface via diurnal mixing. With the recouping of winds after daybreak, the influence of the strengthening pressure gradient will be felt across the region with breezy to gusty northeasterly winds, especially picking up during the afternoon hours. The enhancement of onshore winds will create a notable temperature gradient across the region this afternoon with forecasted high temperatures in the low to middle 80s across the eastern half of the region and highs in the upper 80s (even a few locales potentially reaching 90F) across the western half of the region.

With the negative phase of the North Atlantic Oscillation in full swing, the next longwave trough across the western United States will begin to amplify and pivot eastward today. This will result in the axis of mid-level ridging across the central Gulf to slide eastward over the Florida Peninsula and local waters today into early Saturday. As the longwave trough across the central United States continues to amplify this weekend, mid-level ridging over the Florida Peninsula and adjacent waters will gradually flatten out and weaken. Persistent mid-level northwesterly flow may veer more west- northwesterly or even westerly during this time frame. The axis of expansive surface ridging situated across the eastern United States will advect eastward into the western Atlantic waters, veering local surface flow out of a more easterly direction. This will result in a slight weakening of the pressure gradient on Saturday, although winds will still remain breezy, especially along the east coast of South Florida. Even with winds veering to a more easterly direction and lessening slightly in intensity, there will still be an afternoon temperature gradient across the region on Saturday with forecasted highs ranging from the low to mid 80s along the east coast of South Florida and Lake Okeechobee with temperatures in the upper 80s expected across southwestern Florida.

LONG TERM

(Saturday night through Thursday) Issued at 1225 AM EDT Fri Oct 17 2025

The aforementioned mid-level trough will arrive across the Great Lakes region on Sunday with an associated surface low also pivoting across the region. A sprawling frontal boundary associated with the distant surface low will sweep across the southeastern United States on Sunday and arrive across South Florida during the day on Monday. The ECWMF and GFS have both trended on a less amplified trough but still depict the passage of the subtropical jet over South Florida. While the phasing of the right entrance region of a jet-streak will pass over South Florida during the day on Monday, the lack of ample moisture return and instability across the region appears to keep the threat of more robust convection minimal at this time. During this time frame, high temperatures will trend higher as breezy diurnally easterly flow continues. High temperatures in the low 90s are possible on Sunday and once again on Monday across southwestern Florida with forecasted high temps in the mid to upper 80s across the east coast metro.

As mid-level troughing slides into the western Atlantic waters on Tuesday, the subtropical jet and upstream waves will remain active across the eastern United States as additional lobes of mid-level vorticity amplify and advect eastward across the Great Lakes. Associated surface lows will also advect from west to east across the Great Lakes dragging sprawling frontal boundaries across most of the eastern half of the country. These reinforcing frontal boundaries will remain weak upon arrival to South Florida, with no measurable dip in temperature behind each passage, however they will continue to reinforce the dry airmass in place across the region by keeping surface wind flow out of a northerly direction and ushering in dry air that will gradually mix down in the atmosphere. With a lack of precipitation and ample sunshine, temperatures will remain slightly above average for this time of year during this time frame with forecasted afternoon high temperatures each day during the middle to late park of the week remaining in the upper 80s to low 90s each afternoon.

AVIATION

(06Z TAFS) Issued at 1225 AM EDT Fri Oct 17 2025

Winds will remain light out of a northeasterly direction this morning before becoming gusty late this morning into the early afternoon hours. SHRA across the nearby Atlantic waters will decrease over the next several hours, with mostly VFR and dry conditions expected throughout the TAF forecast period.

MARINE

Issued at 1225 AM EDT Fri Oct 17 2025

Northeasterly winds will remain fresh to strong today and Saturday before lessening during the second half of the weekend and veering more east-southeasterly. The continued arrival of northeasterly swell interacting with the Gulfstream current will result in seas remaining in the 5-7 feet range across our Atlantic waters today into early Saturday. Seas across the Gulf waters will range from 2 to 3 feet today, increasing to the 3 to 5 feet range by Saturday. A few isolated showers are possible across our local waters during the first half of today before drier conditions are expected across the region during the first half of the weekend.

BEACHES

Issued at 1225 AM EDT Fri Oct 17 2025

A high risk of rip currents will continue across all east coast beaches of South Florida today. With breezy onshore winds and a northeasterly swell arriving along our coast, the high risk of rip currents for the east coast of South Florida will continue through at least Sunday evening.

HYDROLOGY

Issued at 1225 AM EDT Fri Oct 17 2025

The combination of higher than normal tidal levels due to the lunar cycle, enhancing onshore flow, and northeasterly swell will result in the continued potential of minor coastal flooding within 1.5 to 2 hours of high tide along the east coast over the next several days. A Coastal Flood Statement remains in effect for coastal Miami-Dade, Broward, and Palm Beach counties through at least Sunday evening.

PRELIMINARY POINT TEMPS/POPS

Miami 84 73 84 74 / 0 0 0 0 West Kendall 85 70 85 71 / 10 0 0 0 Opa-Locka 85 71 85 73 / 0 0 0 0 Homestead 84 72 84 74 / 10 0 0 0 Fort Lauderdale 83 73 83 74 / 0 0 0 0 N Ft Lauderdale 84 73 83 74 / 0 0 0 0 Pembroke Pines 86 72 86 74 / 0 0 0 0 West Palm Beach 84 72 83 73 / 0 0 0 0 Boca Raton 84 72 84 73 / 0 0 0 0 Naples 88 68 88 70 / 0 0 0 0

MFL WATCHES/WARNINGS/ADVISORIES

FL...High Rip Current Risk through Sunday evening for FLZ168-172-173.

AM...Small Craft Advisory until 2 AM EDT Saturday for AMZ650-670.

Small Craft Advisory from 5 AM early this morning to 2 AM EDT Saturday for AMZ651-671.

GM...None.