Typhoon Maria, after blasting across the southern Japanese Ryukyu Islands, is now moving just north of Taiwan, delivering very heavy rain to much of the island, including Taipei City. It’s next and final destination is mainland China.
According to the Joint Typhoon Warning Center, maximum sustained winds at 1500 UTC Tuesday were estimated near 120 mph, with gusts to 150 mph (~195 kph/240 kph, respectively). The system is forecast to make landfall on the mainland Chinese coast by between 3-6 UTC Wednesday (10 pm-1 am CDT Tuesday/Wednesday in the US, 11 am-2 pm Wednesday Taipei, Taiwan time).
As sea surface temperatures lower gradually approaching the Chinese coast, Typhoon Maria will continue to weaken gradually. The sea surface temperatures in Maria’ s path are mostly running near normal. However, at 81 F/27 C, it is more than warm enough to support a tropical cyclone of moderate strength.
It is expected to make landfall as a Category 2-equivalent typhoon (forecast sustained winds 100 mph/~160 kph) . Because the system will remain relatively well organized, this will continue to be a “all-hazards” event; potentially torrential rainfall, damaging wind gusts in excess of 100 mph near the large eye, significant storm surge, particularly in bays and battering waves in excess of 33 ft/10 meters on top of the surge.
Potentially life-threatening risks from these hazards include injuries from falling or flying debris in the intense winds, very dangerous inland flooding from the heavy rains and storm surge flooding from the landfall of the typhoon, as well as the battering waves on top of the surge.
The North Atlantic tropics finally woke up after a weeks long period of dormancy…with the birth of Tropical Storm Beryl Thursday. The system formed in the west-central Atlantic after days in a formative stage as a tropical wave with no defined surface low.
Beryl is a very small system with tropical storm force winds only extending out 35 miles from the center of circulation Thursday night. However, it has continued to strengthen through Thursday Night and is expected to become a minimal hurricane later Friday.
Although the system is depicted to move near the Lesser Antilles late-Sunday, vertical wind shear…increasing wind speed with height…is expected to increase dramatically over Beryl as it approaches Sunday, leading to a rapid weakening and possible dissipation. This is highly likely given the small size of the circulation. However, regardless of what the status of the system is when it moves over the islands, accompanying what remains will be gusty winds, showers and thunderstorms and local downpours.
Meanwhile, in the Western Pacific, Maria has become a Category 5-equivalent super typhoon with maximum sustained winds of 160 mph. The first Category 5-equivalent cyclone observed in either the North Pacific or North Atlantic in 2018. Maria moved over Guam and the southern Mariana Islands as a tropical storm, bringing strong winds and locally heavy rainfall. Damage was reported to Rota’s power system, but no damage to personal property or injuries were reported. The system then became a typhoon west of the island chain, before rapidly intensifying to a Category 3-equivalent typhoon around 1800 UTC (1 pm CDT Thursday in the US), then to its present intensity (as of this post) several hours later.
Maria is expected to move generally northwestward over open water during the next three days. It will remain a powerful typhoon thanks to absolutely steamy waters warmer than 90 F/32 C, 1 C or more above normal. Afterwards, it will move over slightly cooler waters, but may remain a powerful Category 3 or 4 hurricane (115 mph+ winds) as it approaches some of the southern most small Japanese islands on Tuesday.
The most significant threats from Maria will be increasing high surf and rip currents for areas ahead of Maria (Philippines, southern Japan, Taiwan) followed by heavy rainfall and damaging winds for the remote southern Japanese islands as it moves closer toward mainland China midweek.
The North Pacific and North Atlantic appear to be fairly quiet as far as significant ocean storms. However, I wanted to make note of a likely developing tropical cyclone in the Eastern Pacific Basin (east of 140 W longitude). The US National Hurricane Center has pegged it with a 80% chance of development over the next 2 days before it moves northward toward much colder waters after Monday. It should be no threat to land at this time.
A couple of other tropical waves are ongoing east of the one mentioned above; one south of mainland Mexico, another offshore Central America. Numerical models indicate the two waves may merge and possibly form a tropical cyclone the second half of next week (after Tuesday). There’s also appears to be a favorable signal for elevated tropical cyclone development in the Eastern Pacific starting mid-week going into early the following week. Details become sketchy that far out of course, beyond the general pattern set up. The active pattern signals forecasters look for are 1) active monsoon trough…the convergence zone for abundant thunderstorm activity from Central America out over the very warm waters of the Eastern Pacific, 2) active Central American Gyre which provides thunderstorm complexes with mild spin as they move from land over open water, and 3) a low wind shear environment over the open ocean for systems to form without disruption. And with more cyclones means greater risk for landfall impacts as were seen with Bud and Carlotta. Waters over the basin continue to be abnormally warm (1-1.5 C/2-3 F above normal generally) relative to mid to late-20th century norms.
So something to watch later next week for more significant impacts to either Mexico or the Southwest US for remnant moisture yet again.
An unusually potent (for the time of year) North Atlantic frontal system impacted British Isles and Ireland this morning and afternoon (local time) with intense winds and locally heavy rainfall. Ireland and Scotland were particularly hard hit with gusts to 80-90 mph (isolated gusts to 100 mph) during the morning and early afternoon hours Thursday.
The BBC reported that the highest wind gust ever recorded in the month of June in Northern Ireland occurred this morning; a hurricane-force wind gust of 74 mph at Orlock Head. Edinburgh, Scotland reported a gusts near 60 mph, as did Leeming Royal Air Force Base in northern England. Great Dun Fell, a 2,782 ft mountain in northern England reported a gust at its peak of 95 mph. With trees fully bloomed with leaves in mid-June (especially thanks to the recent very abnormally warm weather in Britain), large trees act as sails to the wind and are more easily toppled, posing life-threatening hazards from falling trees or branches onto roads. And this was much the case today with trees falling in the strong winds and heavy rain spreading over the north.
The Eastern Pacific tropical cyclone Bud has, as expected, continued its rapid weakening is now a dying tropical storm with maximum sustained winds of 45 mph. It has lost much of its deep convection, but still has a prominent circulation with gusty winds and locally heavy rain bands with scattered thunderstorms.
Bud is expected to make landfall near Cabo San Lucas late tonight as a very minimal tropical storm or depression (likely 35-40 mph winds) as it continues to track of waters with little heat to support heavy thunderstorm activity. It will then move over the southern Peninsula and into the Gulf of California for mainland Northwest Mexico Friday as a weakening depression.
As the systems enters the Gulf, its moisture, plus additional low-level moisture will rapidly surge northward from the Gulf, leading to increasing showers and thunderstorms in parts of Arizona, New Mexico and farther northward. Flash flooding is possible from these storms.
I would also mention, given the very dry soils and very dry air ahead of the system, more isolated storms may produce intense downbursts of cooler strong winds which may induce dust storms, so be mindful of this if they develop.
I will also give special mention to the surge of tropical moisture expected into Texas and Louisiana Sunday into early next week. Heavy rainfall and flash flooding will be possible in parts of Southeast Texas and Southwest Louisiana.
I’ll have more on this event this weekend, as it’s associated with a marginal risk of tropical development in the Bay of Campeche tomorrow or Saturday. But regardless, heavy rainfall will be the biggest issue with this event.
Hurricane Bud strengthened to a Category 4 hurricane on the Saffir-Simpson Wind Scale with maximum sustained winds of 130 mph overnight. The update released at 8 am PDT by the National Hurricane Center has now downgraded back to Category 3 with 125 mph winds. With ocean heat content (which accounts for warmth with depth) dropping off quickly farther to the north, Bud has likely begun a weakening trend which will likely take it below major hurricane status by tonight and weaken it to a minimal hurricane by tomorrow.
As Bud approaches the southern tip of Baja on Thursday, rainfall and high surf will increase over the area. I expect tropical storm watches to be put up over southern Baja California Peninsula by this evening. The biggest threat to southern Baja will be locally heavy rain from rain bands and high surf. The system will likely be a dying tropical storm by the time it arrives near Cabo San Lucas Thursday night.
Again, still expecting a moisture surge up the Gulf to generate increasing monsoon showers and thunderstorms into northern Mexico and Southwest US this weekend. Watch out in these areas for potential flash flooding concerns.
Checking in on the Atlantic…there’s a very slight chance of tropical development in the western Caribbean during the next 5 days (20% according to the National Hurricane Center). However, regardless of development, it appears a pattern is setting up for a significant surge of deep moisture from the Caribbean into Texas early next week, potentially bringing significant rainfall and possibly flooding. Texas is currently facing growing drought conditions.
I’ll keep an eye on things, but regardless, I would be mindful of heavy rainfall in the forecast later this weekend and early next week if you live in Southeast Texas into Louisiana and perhaps farther north. I’ll keep an eye on things!
Hurricane Bud has continued its robust intensification, as expected, now a Category 3 hurricane (at 8 am PDT) based on satellite intensity estimates with maximum sustained winds of 120 mph and gusts to 150 mph.
The hurricane continues to show strong blow ups of thunderstorms with very cold cloud tops in its inner core region known as the “central dense overcast” or CDO Region indicating that it is continuing or organize and additional strengthening may occur during the day today into this evening.
As mentioned last night, given the thermodynamic environment (abnormally warm waters below unstable air above for air to rise), low wind shear (winds not increasing in speed with height so the low pressure system remains “vertically stacked”) and favorable poleward outflow (air from the surface low being sent up upper atmosphere and blown off generally northward and away, allowing surface low to intensify further), there’s little to stop Bud from strengthening further, except for the system itself. Unpredictable structural changes in its eyewall could inhibit further strengthening, but for now that doesn’t appear to be imminent. However, by tomorrow, the steering currents are forecast to slow down somewhat and its own powerful inner core may act as a “negative feedback” and cool the waters under it as a result of upwelling of colder water from greater depths not as well heated by sunlight. This will likely result in a gradual weakening. After this, it will also begin to traverse somewhat lower temperature waters already on the surface itself, limiting any opportunity for re-intensification as it approaches the Baja California Peninsula late-week. So an overall weakening trend should begin after Tuesday.
It appears the hurricane’s tropical storm-force wind field will largely stay offshore the Pacific coast of mainland Mexico, although gusts of 40+ mph are certainly possible in gusts as the rain bands hug the coast line near Manzanillo and points with a couple hundred miles north and south over the next 48 hrs. The system should pull away from land the tropical storm watch area after Tuesday and the threat of locally heavy rain and gusty winds will diminish (rip currents and heavy surf will continue) and the threats will shift and increase for the Baja CA Peninsula. There has been a trend in some numerical models to track the to system more toward the southern tip of Baja or slightly towards the Gulf of California. Any track farther away from the open Pacific waters would mean more of its circulation over warmer waters (compared to the more open Pacific) for more thunderstorm activity to keep the system stronger in terms of winds, wave action and heavy rain. So far, given the decrease in ocean heat content and increasing wind shear, this still looks far more like a tropical storm event than a hurricane event for Baja and the possibly the southern Gulf waters. But this would still mean areas of heavy rain, flash flooding and landslides over mountainous terrain and wave hazards along coastal areas. In addition, if Bud moves more toward the Gulf, this may induce a stronger moisture surge up into the Southwest US, enhancing the monsoon flow pattern change and increasing thunderstorm activity.
While *again*, amounts will change depending on the track of Bud, some monsoon-related switch in air flow pattern is expected and if the moisture is as abundant as possible with a very abnormally warm Gulf + remnant moisture from Bud, folks living in the Four Corners region should watch forecasts specifics related to possible thunderstorms and locally heavy rainfall this weekend. Given the extreme to exceptional drought conditions in this region, the soils are likely very dry and hard and heavy rain which falls will not be absorbed as quickly as it would be otherwise (rainfall will help, but too much too soon is bad for rapid runoff). So details can only be found in future forecasts, but it’s something to keep in mind at the moment.
PS: I was just asked a question about the Eastern Pacific Hurricane Climatology compared to how things are going thus far in 2018. Numbers of systems thus far are listed with days, late or normal listed in parentheses). The normal values are based on 1971-2009 baseline. Still very early in the season and early season activity doesn’t necessarily provide clues to future activity.
Tropical Storms: 2 (2nd storm formed 16 days earlier than normal).
Hurricanes: 2 (2nd hurricane formed 34 days earlier than normal).
Major Hurricanes: 2 (2nd major hurricane formed 69 days earlier than normal).
For the North Atlantic, which is quiet at the moment (based on 1966-2009 baseline):
Tropical Storms: 1 (1st storm formed 45 days earlier than normal).
Bud is now a hurricane (Category 1 on the Saffir-Simpson wind scale as of this post) and expected to intensify as it moves over waters in the mid-80 F (28-29 C). With these very warm waters and weak vertical wind shear, I expect robust intensification during the next day or two. Steering currents will take take the system much closer to Mexico, making direct impacts by wind, wave action and rainfall likely vs. Aletta which stayed completely offshore. As a result, the government of Mexico has issued a tropical storm watch for a portion of the mainland Pacific coast from Manzanillo to Cabo Corrientes.
The tropical storm watch covers the possibility that the tropical storm force wind field…with sustained winds of 39 mph or greater…may graze the coastal communities late-Monday through late-Tuesday. Based on the as the track suggests, the system could also threaten Baja California by the end of the week. The system will likely go through its period of robust intensification through the next 24-36 hrs. Based on satellite trends tonight and the upper-level environment, I think it becoming a Category 4 hurricane (130 mph+) is not out of the question. Satellite estimates suggests the system may be approaching Category 2 (96-110 mph) status already. A stronger hurricane could mean a larger wind field and higher waves threatening more of the Pacific coast.
While it is still too early to determine the full impact that Bud will have on the Baja Peninsula, given the abnormally warm waters, it will likely be an organized cyclone with rain bands and some wind, but yet likely to weaken thanks to increasing vertical wind shear farther north. Although there’s a likelihood Bud will become a major hurricane, its slow forward motion over the next few days may induce cold upwelling, inducing earlier weakening than would otherwise occur. I think the likelihood of a Bud bringing hurricane-force winds to the Peninsula as low at this time.
So anyone traveling to the mainland areas, be mindful of locally heavy rainfall, rip currents and strong winds in the tropical storm watch area Monday-Tuesday. The southern tip of Baja California will know more about their threats by Tuesday.