WxWatcher007

I have two tweets/images that may be helpful in understanding where we are and where we’re going. The first is a hovmoller to understand the gradual expansion of the wind field. Although Milton’s inner core had remained small, the annotated image below makes it clear that the wind field overall has grown over time. This is going to continue as the storm approaches the coast. At this point, major to catastrophic surge is almost certainly set in motion for wherever that maximum zone sets up. It’s why folks under evacuation orders needed to heed those warnings—as I said this morning, we still cannot know the exact landfall zone and as such folks should anticipate the worst and take action now rather than wait until a few hours before landfall. The second is also very important imo: it’s a cross section of the core. Andy does a great job of pointing out how exceptionally strong and deep this inner core is. In a vacuum, this has two implications imo 1) This kind of core could be quite resilient to increasing shear. 2) This deep a vortex could be more apt to move poleward as it turns NE and feels the influence of the trough. We’re not in a vacuum however. I think a lot of what happens with track and intensity will depend on when and how long an ERC takes place. It’s still a small core, that can ramp up or down quickly. An ERC late tomorrow, as shear is increasing, may very well weaken the vortex substantially, leading to a weaker storm that tracks further south. If, however, we get an ERC to begin overnight and complete quickly, it would expand the vortex, making it more inertially stable and resistant to shear that arrives when the vortex is less vulnerable, which would potentially hold the intensity at wherever the ERC leaves it, and make jogs north more likely, especially if the convection becomes “weighted” to the northern section. These aren’t major shifts. But they may make the difference between a landfall at 120mph and maybe 135mph, or south/north of Tampa. Just my evening thought. I don’t know which side we’ll end up on. Edit: for the FL folks, I’m just using Tampa because that’s really the dividing line on center potential. Obviously, a further south impact would be major to catastrophic for Sarasota, Port Charlotte, and even Ft. Meyers if this trends south late, which is possible as well.

Latest VDM has a central pressure of 916mb with a 6nm wide eye and a peak FL wind of 142kt.

Hasn’t been much discussion here of the inland flash flood risk but hopefully local folks are getting the message.

Product: NOAA Temp Drop (Dropsonde) Message (UZNT13 KWBC)Transmitted: 9th day of the month at 0:20ZAgency: National Oceanic and Atmospheric Administration (NOAA)Aircraft: Lockheed WP-3D Orion (Reg. Num. N42RF)Storm Name: MiltonStorm Number: 14 (flight in the North Atlantic basin)Mission Number: 17Observation Number: 10 ( See all messages of this type for this mission. )Part A... Date: Near the closest hour of 23Z on the 8th day of the month Highest Mandatory Level For Which Wind Was Reported: 850mb Coordinates: 22.8N 87.0W Location: 114 statute miles (183 km) to the N (355°) from Cancún, Quintana Roo, Mexico. Marsden Square: 081 ( About ) Surface and Standard Isobaric Surfaces Level Geo. Height Air Temp. Dew Point Wind Direction Wind Speed 1000mb This level does not exist in this area of the storm above the surface level. 927mb (27.38 inHg) Surface (Sea Level) 24.8°C (76.6°F) 24.6°C (76°F) 155° (from the SSE) 160 knots (184 mph) 925mb 23m (75 ft) 24.8°C (76.6°F) 24.7°C (76°F) 155° (from the SSE) 169 knots (194 mph) 850mb 766m (2,513 ft) 22.0°C (71.6°F) 22.0°C (72°F) 210° (from the SSW) 151 knots (174 mph) Information About Radiosonde: - Launch Time: 23:10Z - About Sonde: A descending radiosonde tracked automatically by satellite navigation with no solar or infrared correction. Remarks Section... Dropsonde Location: Dropped in eyewall 135° (SE) from the eye center. Highest altitude where wind was reported: - Location: 22.85N 86.99W - Time: 23:10:35Z Lowest altitude where wind was reported: - Location: 22.93N 86.92W - Time: 23:13:25Z Mean Boundary Level Wind (mean wind in the lowest 500 geopotential meters of the sounding): - Wind Direction: 180° (from the S) - Wind Speed: 154 knots (177 mph) Deep Layer Mean Wind (average wind over the depth of the sounding): - Wind Direction: 215° (from the SW) - Wind Speed: 135 knots (155 mph) - Depth of Sounding: From 753mb to 926mb Average Wind Over Lowest Available 150 geopotential meters (gpm) of the sounding: - Lowest 150m: 158 gpm - 8 gpm (518 geo. feet - 26 geo. feet) - Wind Direction: 160° (from the SSE) - Wind Speed: 165 knots (190 mph) Sounding Software Version: AEV 40002 Part B: Data for Significant Levels... Significant Temperature And Relative Humidity Levels Level Air Temperature Dew Point 927mb (Surface) 24.8°C (76.6°F) 24.6°C (76°F) 850mb 22.0°C (71.6°F) 22.0°C (72°F) 764mb 18.4°C (65.1°F) 18.4°C (65°F) 758mb 19.4°C (66.9°F) 17.3°C (63°F) 750mb 18.0°C (64.4°F) 17.7°C (64°F) Significant Wind Levels Level Wind Direction Wind Speed 927mb (Surface) 155° (from the SSE) 160 knots (184 mph) 926mb 155° (from the SSE) 162 knots (186 mph) 925mb 155° (from the SSE) 170 knots (196 mph) 924mb 155° (from the SSE) 164 knots (189 mph) 922mb 155° (from the SSE) 174 knots (200 mph) 921mb 160° (from the SSE) 178 knots (205 mph) 918mb 160° (from the SSE) 174 knots (200 mph) 913mb 175° (from the S) 149 knots (171 mph) 906mb 185° (from the S) 160 knots (184 mph) 893mb 190° (from the S) 153 knots (176 mph) 879mb 195° (from the SSW) 156 knots (180 mph) 873mb 200° (from the SSW) 147 knots (169 mph) 867mb 200° (from the SSW) 145 knots (167 mph) 850mb 210° (from the SSW) 151 knots (174 mph) 753mb 255° (from the WSW) 144 knots (166 mph) Dropsonde Diagram 0102030401000925850700Temperature (°C)Pressure Level (mb)Dew PointAirWind (kts)Milton (14L)Mission 17 - NOAA2Time: 23:10Z on 8th day of monthObservation Number: 10Location: 22.85N 86.99W

This may be helpful. There are a number of factors that drive surge height. https://www.weather.gov/media/owlie/surge_intro.pdf

Down to 902mb. It seems more or less steady state, maybe some slight intensification with the continued pressure fall. We’ll see if it can tick below 900 again.

With a 159kt FL wind.

Leslie is back! A hurricane again at 5pm.

No doubt in my mind it’s a 5 again. Truly incredible to witness in the Gulf at this time of year.

Yeah these satellite estimates only take you so far. I’m looking forward to recon.

Well…it speaks for itself. As good a look as anything yesterday.

Definitely worth a watch.

Thanks. Definitely not a met, just been studying tropical since I was a kid. Literally.

I think the skyrocketing temperature graph above says it all. Like @CoastalWxsaid, sometimes you just need to tweak conditions to change the outcome and there’s no doubt Milton is intensifying right now given the recon data and increasingly impressive satellite presentation. Yesterday was surprising, but today is where we could see that peak barring an ERC at this point.

NHC says it doesn’t have much time to acquire (sub)tropical characteristics. Interestingly, these baroclinic lows have struggled to become tropical this year.

I think the recon data on that last fix (still waiting for VDM) along with the unambiguous clearing and warming of the eye supports at least 155mph at 2pm, if not an upgrade to 160. I could see them waiting until the next recon though.

Recon reporting FL winds of 145kt on that latest pass.

Well I had no idea my post in the main tropical thread would be that popular lol. It’s nice to add value.

A worthwhile read from one of the best

The NHC settles it. Not surprising to see conflicting viewpoints when there’s conflicting data. Sequences of microwave images and recent Hurricane Hunter observations suggest that Milton completed an eyewall replacement overnight, and the new eyewall has contracted down from 22 n mi to 12 nm in diameter. However, it does not appear that the hurricane weakened much after the eyewall replacement, and it could have rebounded with the outer eyewall contraction. A dropsonde released by the NOAA P-3 in the northeastern eyewall recently measured an average wind of 156 kt in the lowest 150 m of the sounding, which equates to an intensity of 130 kt. The latest pressure reported by the planes is 929 mb.

Yeah, it looked like the FL winds went up in one of the flights to 144kt, but the IR and data hasn’t suggested intensification since. The lightning may be a precursor to intensification but that’s not enough evidence for me. It’ll be interesting to see if it can in fact reintensify today.

My personal belief remains that this will end up further north, probably near Clearwater as you said yesterday, but we’ll see.

Let’s try to take a more comprehensive look at Milton this morning. Overnight, Milton completed an Eyewall Replacement Cycle in which the winds came down from their exceptional peak and the pressure rose from a staggering 897mb to 924mb. This morning’s recon flight has the latest VDM showing 932mb, though indications are this is starting to fall again. In my estimation, Milton is starting to reintensify. In the last few frames you can see a warmer and more defined eye, and until shear picks up, I think the only thing slowing this down over the coming hours will be if another ERC attempt begins. The VDM also had the new eye at 12nm, so the intensification rate could be substantial today. Milton is gaining latitude and as frustrating as it may be, we are not at a place yet to know the final landfall location, which matters immensely for coastal communities. But first, I want to talk other impacts. Wind The radius of maximum winds is still pretty small. Hurricane force winds only extend out 30 miles per the 5am advisory. This may help Milton try to reach a second peak today, but every expectation is that as this gains latitude and makes its final approach the wind field will grow substantially. As a result, in addition to higher wind speeds due to a major hurricane landfall, hurricane force gusts are likely across the peninsula in the path of the storm, hence the hurricane watches and warnings. Given the metropolitan areas in the path, damaging winds will likely cause widespread damage—you don’t need cat 4 winds for that. At the landfall point at the coast, it’ll just make things worse. HAFS-A shows the expansion of the wind field in a way that makes sense to me. IMO as we saw with Helene it’s far worse to have lower peak winds reach a larger section inland than extremely high winds only reach a narrow section of coast. Now Pre-landfall Aerial Flooding I’ve been talking about this since the beginning and I’ll keep doing so. We can’t underestimate the aerial flood risk. Now we have a High Risk for excessive rainfall for much of central Florida, extending into Orlando. This kind of flooding gets underestimated and kills as a result in many storms. Inland folks need to understand this risk and be prepared to take action if they are in a low lying area. Edited to add more detailed version of above graphic Surge The surge potential is likely already guaranteed to be met somewhere. Unfortunately, Milton’s intensity, growing size, and heading will bring Major to catastrophic surge to some portion of the west coast of Florida. Given the still fresh damage of Helene, the structural damage could be even more profound. Even on the east coast there will be surge, but the main focus is rightfully on the west coast. This, is where track matters so much. It’s extremely important to not get locked into one solution or even model suite trend yet. If you’re in the potential path prepare as if the worst is coming to you. The 00z super ensemble shows us that a lot of real estate is still at risk of the direct hit. This will likely shift only slightly, but enough to make a huge difference for places like Tampa, Sarasota, and Ft. Meyers. I not only think we’re still searching for that final landfall point, we also have to be abundantly clear eyed about the fact that given the angle of approach, wobbles—which are common features near landfall—can dramatically change where the worst surge ends up. Folks I cannot make it more clear—you can have a spot on NHC forecast that’s still off by 10-25 miles. Nobody should be locking in a landfall point at this range. Timing, which also hasn’t been nailed down to the hour, matters here too for high/low tide. The bottom line is that this is a multi-hazard dangerous storm, even inland. I think we see a run at another peak today before shear and another ERC fully disrupt the intense inner core. I do think that we see weakening before landfall, but with an expanded wind field and Milton coming off a high peak, a landfall intensity of 125-135mph remains a reasonable possibility. We don’t know yet where the landfall point will be, and honestly, I don’t think we’ll truly know that until a few hours before landfall. To anyone in the path that’s still on the fence about the seriousness of this one—get off of it. This is as serious as it gets. Hope this long post helps some.