sausiuswx.bsky.social
@sausiuswx.bsky.social
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Average weather enthusiast - Main areas of interest: Tropical Cyclones and (European) severewx
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And for folks who are on Jamaica. I can only say that I hope yall are hunkered down somewhere reasonably safe. There is nothing anyone on Jamaica can do now anymore. Conditions outside do not safely permit any further preperations anymore. All you can do is hope and pray.
The key messages wording for Melissa is as serious as it gets. This is a storm like non other Jamaica has experienced, certainly in living memory, possibly even in the history of the nation. To all my followers who are relligious, I recommend you pray for folks there. (1/2)
BREAKING NEWS: According to the newest NHC advisory, Melissa has now become the extremely rare 3rd Category 5 hurricane of the 2025 Atlantic Hurricane season. Expected to make a potentially devestating landfall in Jamaica at (nearly) unabaited intensity tomorrow morning.
Recon has now captured FL winds supporting Category 5 force winds at the surface (154*0.9 = 138.6 kts) in the likely weaker southern Eyewall. The XTRAP pressure is even lower as well and now around 917 mbar. Melissa likely a cat5 now.
We are two for two now on Objective Dvorak (ADT) fixes with CI numbers over T8.0 for Melissa now. Wow, just wow!
(Just satellite estimates, recon = king)
NCCF DVTO T8.1 = 173 kts (320 km/h, 200 mph). Of course just one objective intensity aid. Recon is king.
Of course the satellite presentation of Melissa remains impeccable and has suggested a category 5 since yesterday. Easily T7.0-7.5 in subjective analysis. Uniform CMG surrounding >20°C pinhole eye (+banding). One objective estimate has even crossed the magical T8.0 threshold.
AF reserve Hurricane Hunters measured 152 kt FL winds in the NE quadrant of Melissa (*0.9=137 kts = cat5 threshold. Pressure in the high 910s to low 920s also compatible with Cat5. What will NHC do? Next advisory in 2 1/2 hrs but out of bounds update for upgrate always possible.
Pressure has dropped bigly since last recon mission (almost 8 mbar). Now into the low 930s. Recon finding FL winds of 129 kts in the eatern Eyewall. Still suggesting winds of at least 115 kts but stronger winds are surely to be found elsewhere in the storm (like on the NE).
The satellite presentation of Melissa is just inmpecable. Gravity waves eminating through the very symmetrical cold CDO surrounding the small highly circular 20°C eye. Very very nice banding on the eastern semicircle as well. Definetely sat presentation of a high-end hurricane.
The satellite presentation has also improved if anything since the last advisory. Of course none of the wind data suggested intensities up to 130 kts but always remember that those are always representing the floor of what is present within the storm, due to undersampling.
Interestingly the objective and subjective dvorak estimates all suggest that Melissa is a category 5. AiDT and D-PRINT also agree. Therefor NHC may go with 125-130 kts at the next advisory, esp. considering that the pressure has decreased again throughout the last mission. (1/2)
The eye is now warmer (>18°C) and contracting slightly. The CDO also remains very cold and symmetrical, contracting ever so slightly as well. Neat banding continues on the eastern side. Under the hood merger EWRC may be occuring. Melissa continues on course for Cat5 intensity.
The pressure has started dropping again and is now in the low 940s but there is still no evidence from the wind side that the winds have increased beyond 120 kts. It does look however look like Melissa is done taking a break and is now strengthening once more.
Latest recon data further confirms the notion that the intensity of Melissa has levelled off for the time being. In fact NHC estimate remains slightly bullish compared to aircraft data. Wind measurements more in line with 110-115 kts. Pressure compatible with 115-120 kts.
For Folks in Jamaica, your time is up! It is now time to hunker down and hope for the best. Torrential rain capable of causing catastrophic and life-threatening flash flooding and numerous landslides begins today, followed by potentially devestatig winds beginning Monday night.
NHC doesn't however seem to see any direct evidence for imminent eyewall replacement and such evidence is certainly not known to me either. W Shear could actually work against this, in preventing concentric bands from fully wrapping around the core and enclosing the inner eyewall
The intensity of Melissa has seemingly levelled off today, according to recon data from this morning (tho a new mission is investigating rn). The effects of some W shear are still evident. NHC also reporting occasional breaks in the eyewall and some concentric banding.
The waters of the central carribean are like rocket fuel for tropical cyclones and have catapulted Melissa from a high end tropical storm to a category 4 monster. A stunning metamorphosis. Seems like only internal processes could slow her down. Jamaica is in big, huge trouble.
The satellite presentation of Melissa is now evolving very rapidly indeed. Needless to say that Melissa now has her foot firmly on the loud pedal and is in the midst of an impressive period of rapid infensification that will see her become a major hurricane in no time at all.
Tail mounted doppler radar data for Melissa supports a fairly symmetrical windfield actually and aligns very well with the NHC fix of 85 kts (92.5*0.9= 83,25). Data also shows the solid, closed eyewall. Structure poised for further rapid intensification for sure.
Preliminary recon data suggests that Melissa may already a category 2 on the SSHWS. At the very least she is on the cusp. The 97 kts FL winds come out to about 85-90 kts at the surface (87.3 to be precise). The XTRAP MSLP of 970.8 would also support that.
To expand on this, on thursday I already said that NHC key messages hardly come more strongly worded. Well, they have upped the anti even further. It is important to stress that NHC does not choose their words lightly. THIS IS A LIFE THREATENING SITUATION FOR JAMAICA & SW HAITI!
The newest rainfall forecast for Melissa is just horrific frankly. WPC now forecast more then 30 in of rain in parts of E Jamaica over the next 4 days. Possibly up to 40 in, that would be 1000 l/m2 (mm)! Just wow! The results of this in Jamaica and SW Haiti won't be pretty at all
Melissa has now finally been made a hurricane by the NHC. Rapid intensification into a high-end tropical cyclone and a catastrophic near cat5 landfall in Jamaica are expected. The threat of life-threatening flooding will already precede this over the weekend there and in SW Haiti