Dare to hope: With the demise of catastrophic Hurricane Iota on Wednesday, the terrible 2020 Atlantic hurricane season may have finally had its last deadly storm. The Atlantic hurricane season officially ends on November 30, but it is likely there will be no more deadly Atlantic storms in 2020. One or more weak named storms, perhaps staying out to sea, are still likely to form before the end of the year, but these are unlikely to cause mass destruction or loss of life.
Unfavorable conditions loom in tropical Atlantic
Sinking air over the tropics leads to drying, high pressure, and reduced odds of tropical storm formation – that’s exactly what is expected over the tropical Atlantic through early December given a state of the Madden-Julian Oscillation (MJO) unfavorable for Atlantic tropical cyclones.
The MJO is a pattern of increased thunderstorm activity near the equator that moves around the globe in 30 to 60 days; odds of tropical cyclone formation increase when the MJO is strong and suitably located, but typically decrease for ocean basins not in the active portion of the MJO. During the formation of Hurricane Eta, the MJO was in a favorable place for enhancing Atlantic tropical cyclones, but it was transitioning to an unfavorable state when Hurricane Iota formed. It is expected to remain unfavorable into early December.
Favoring tropical cyclone formation in the coming weeks will be above-average ocean temperatures in the tropical Atlantic, plus an intensifying La Nina event in the eastern Pacific, which will contribute to below-average levels of wind shear over the tropical Atlantic. However, the current unfavorable state of the MJO, plus the near end of the climatological close of hurricane season, argue that the 2020 Atlantic hurricane season at last may have had its final deadly storm. That prediction is bolstered by the fact that over the past few days, multiple runs of the top three models for forecasting tropical cyclone genesis have not predicted formation of any new tropical storms through the end of November.
In a season with a proven track record for spitting out record numbers of named storms (30 so far), 2020 will still be able to produce one or more relatively inconsequential tropical or subtropical storms before the end of the year, perhaps resulting in a final nearly unfathomable tally of 31-33 named storms in this busiest-ever season on record.
The previous record-busy Atlantic hurricane season, 2005 with 28 named storms, had three named storms form after November 20: Tropical Storm Delta on November 22, Hurricane Epsilon on November 29, and Tropical Storm Zeta on December 30. None of those storms caused loss of life while they were named, although Delta killed seven people in the Canary Islands after it had transitioned to an extratropical storm. Only three deadly December tropical cyclones have been recorded in Atlantic history:
Tropical Storm Odette, Dec. 4-7, 2003, 8 killed in the Dominican Republic;
Hurricane Four, Dec. 1, 1925, 60 killed in Florida; and
Unnamed Hurricane, December 1779, 120 killed on ships in the Atlantic.
Two tropical disturbances to keep an eye on
An area of low pressure that formed on Wednesday over the southwestern Caribbean was bringing heavy rains to Panama and Costa Rica on Thursday. There is little model support for development of this disturbance, though it will likely bring 4-8 inches of rain to Panama and Costa Rica through Tuesday, as the system moves slowly west to west-southwest across Central America and into the Northeast Pacific. In a 1 p.m. EST Thursday tropical weather outlook, the National Hurricane Center gave 2-day and 5-days odds of development of near 0% to this disturbance.
Also worth watching are the waters off the U.S. East Coast between the Bahamas and Bermuda, where models predict that an area of low pressure capable of becoming a subtropical storm may form by Monday as it moves rapidly to the northeast past Bermuda. In a 1 p.m. EST Thursday tropical weather outlook, NHC gave 2-day and 5-days odds of development of near 0% and 20%, respectively, to this disturbance.
The next name on the Atlantic list of storms is Kappa, the 10th letter in the Greek alphabet.
*Details on Figure 1: The amount of rising or sinking air can be inferred from the 200 mb velocity potential (VP) departure from average (also called the anomaly). Negative 200 mb VP anomalies mean that upper-level winds at the 200 mb level are diverging, causing rising air from below to replace the air diverging away at high altitudes. This rising air helps nurture thunderstorm updrafts, and favors low pressure and increased chances of tropical cyclone formation. Conversely, positive 200 mb VP anomalies imply converging air aloft, where sinking air, high pressure, and dry conditions will be unfavorable for tropical cyclone formation. In this plot, negative 200 mb VP anomalies (divergence) are cool-colored contours (the scale shows the departure from average in standard deviations); positive 200 mb VP anomalies (convergence) are warm-colored contours.
Editor’s note: Unless Tropical Storm Kappa forms, this “Eye on the Storm” blog and focus on Atlantic hurricanes soon will go into winter hibernation. Jeff Masters plans to post a wrap-up piece on the Atlantic hurricane season on November 30 or December 1, after which he and Bob Henson will continue writing often at this site on extreme weather and climate change and on other climate change issues as part of their ongoing “Eye on the Storm” features.
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Posted on November 19, 2020(3:53pm EST).
India Meteorological Department
Tropical Cyclone Advisory #9 – 17:30 PM IST December 1 2020
CYCLONIC STORM BUREVI (BOB05-2020)
==============================================
Cyclone Alert for southern Tamil Nadu and southern Kerala coasts (YELLOW MESSAGE)
At 12:00 PM UTC, The Deep Depression moved west northwestwards with a speed of 9 km/h during past six hours, intensified into Cyclonic Storm ‘Burevi’, and lays centered over southwestern Bay of Bengal near 7.9N 84.8E, about 400 km east southeast of Trincomalee (Sri Lanka) and 800 km east southeast of Kanniyakumari (India).
It is very likely to intensify further during next 12 hours. It is very likely to move west northwestwards and cross Sri Lanka coast between 7.5N and 9.0N, close to Trincomalee during evening/night of December 2nd as a cyclonic storm with a wind speed of 40-45 knots gusting to 50 knots. It is very likely to move nearly westwards thereafter, emerge into Gulf of Mannar and adjoining Comorin area on 3rd December morning. It would then move nearly west southwestwards and cross southern Tamil Nadu coast between Kanniyakumari and Pamban around early morning of December 4th.
Forecast and Intensity
============================
12 HRS: 8.3N 83.4E – 40 knots (Cyclonic Storm)
24 HRS: 8.7N 81.3E – 45 knots (Cyclonic Storm)
48 HRS: 8.8N 79.3E – 40 knots (Cyclonic Storm)
72 HRS: 8.0N 77.1E – 35 knots (Cyclonic Storm)
Surge Warning
—————
Storm surge of about 1 meter height above the astronomical tide is likely to inundate low lying areas of eastern Sri Lanka coast during landfall.
As per satellite imagery, the intensity of the system is T2.5/2.5 with shear pattern. Broken low and medium clouds with embedded intense to very intense convection lay over southern Bay of Bengal between lat 5.0N to 13.5N and 80.0E to 90.0E and also over Sri lanka in association with the system. Minimum cloud top temperature is -93C.
3 minute sustained winds near the center is 35 knots with gusts of 40 knots. State of the sea is very rough to high around the center. The estimated central pressure of the cyclonic storm is 999 hPa.
hello all
Tropical Cyclone Warning Center Perth
Tropical Cyclone Outlook – 2:00 PM WST December 1 2020
========================================
(1) 01U is west of the Western Australia’s area of responsibility and lays centered near 10.5S 87.5E. This low is forecast to continue moving west and remain outside of the Western region.
(2) A tropical low may form in the trough over or just to the south of Java at the end of this week or over the weekend and slowly move south to southwest. There is a LOW risk of this system developing into a tropical cyclone next week. If it were to develop it’s unlikely to have any direct impact on the Western Australia coast.
India Meteorological Department
Tropical Cyclone Advisory #7 – 8:30 AM IST December 1 2020
DEEP DEPRESSION BOB05-2020
==============================================
Cyclone Alert for southern Tamil Nadu and southern Kerala coasts (YELLOW MESSAGE)
At 3:00 AM UTC, The Deep Depression moved westwards with a speed of 11 km/h during past six hours and lays centered southwestern and adjoining southeastern Bay of Bengal near 7.8N 85.7E, about 500 km east southeast of Trincomalee (Sri Lanka) and 900 km east southeast of Kanniyakumari (India).
It is very likely to intensify further into a cyclonic storm during next 24 hours. It is very likely to move west northwestwards and cross Sri Lanka coast between 7.5N and 9.0N close to Trincomalee during evening/night of December 2nd. It is very likely to move nearly westwards thereafter, emerge into Gulf of Mannar and adjoining Comorin area on morning of December 3rd and move westward towards southern Tamil Nadu coast.
Surge Warning
—————
Storm surge of about 1 meter height above the astronomical tide is likely to inundate low lying areas of eastern Sri Lanka coast during landfall.
3 minute sustained winds near the center is 30 knots with gusts of 40 knots. State of the sea is rough to very rough around the center. The estimated central pressure of the deep depression is 1000 hPa.
Over here now. This is going to be quite the change. I feel that I can be content here.
India Meteorological Department
Tropical Cyclone Advisory #6 – 5:30 AM IST December 1 2020
DEEP DEPRESSION BOB05-2020
==============================================
Pre-Cyclone Watch for southern Tamil Nadu and southern Kerala coasts
At 0:00 AM UTC, The Depression moved nearly westwards with a speed of 10 km/h during past six hours, intensified into a deep depression and lays centered over southwest and adjoining southeast Bay of Bengal near 7.8N 86.0E, about 530 km east southeast of Trincomalee (Sri Lanka) and 930 km east southeast of Kanniyakumari (India).
It is very likely to intensify further into a cyclonic storm during next 24 hours. It is very likely to move west northwestwards and cross Sri Lanka coast between 7.5N and 9.0N close to Trincomalee during evening/night of December 2nd. It is very likely to move nearly westwards thereafter, emerge into Comorin area on morning of December 3rd and move westward towards southern Tami Nadu coast.
Forecast and Intensity
============================
12 HRS: 8.1N 84.6E – 35 knots (Cyclonic Storm)
24 HRS: 8.4N 83.2E – 45 knots (Cyclonic Storm)
48 HRS: 8.7N 80.3E – 35 knots (Cyclonic Storm)
72 HRS: 8.5N 78.5E – 40 knots (Cyclonic Storm)
Surge Warning
—————
Storm surge of about 1 meter height above the astronomical tide is likely to inundate low lying areas of eastern Sri Lanka coast during landfall.
As per satellite imagery, the intensity of the system is T2.0/2.0. Center not clearly defined in satellite imagery. Broken low and medium clouds with embedded intense to very intense convection lay over southern Bay of Bengal between 4.5N to 14.5N and 81.5E to 92.5E association with the system. Minimum cloud top temperatures is -93C.
3 minute sustained winds near the center is 30 knots with gusts of 40 knots. State of the sea is rough to very rough around the center. The estimated central pressure of the deep depression is 1000 hPa.
India Meteorological Department
Tropical Cyclone Advisory #5 – 23:30 PM IST November 30 2020
DEPRESSION BOB05-2020
==============================================
Pre-Cyclone Watch for southern Tamil Nadu and southern Kerala coasts
At 18:00 AM UTC, The Depression moved nearly westwards with a speed of 7 km/h during past six hours and lay centered at 2330 hrs IST of 30th November 2020 over southeast and adjoining southwest Bay of Bengal near 7.8°N 86.6E, about 590 km east-southeast of Trincomalee (Sri Lanka) and 1000 km east of Kanniyakumari (India).
It is very likely to intensify further into a deep depression during next 6 hours and into a cyclonic storm during subsequent 12 hours. It is very likely to move west northwestwards and cross Sri Lanka coast between 7.5N and 9.0N close to Trincomalee during evening/night of December 2nd. It is very like to move nearly westwards thereafter, emerge into Comorin area on morning of December 3rd and move westward towards southern Tamil Nadu coast.
Forecast and Intensity
============================
12 HRS: 8.1N 85.3E – 35 knots (Cyclonic Storm)
24 HRS: 8.3N 83.9E – 40 knots (Cyclonic Storm)
48 HRS: 8.5N 80.8E – 35 knots (Cyclonic Storm)
72 HRS: 8.3N 78.4E – 40 knots (Cyclonic Storm)
As per satellite imagery, the intensity of the system is T1.5/1.5. Broken low and medium clouds with embedded intense to very intense convection lay over southern Bay of Bengal between 5.6N to 13.5N and 82.0E to 93.0E in association with the system. Minimum cloud top temperatures is -93C.
3 minute sustained winds near the center is 25 knots with gusts of 35 knots. State of the sea is rough to very rough around the center. The estimated central pressure of the depression is 1002 hPa.
My latest update on Invest 90L in the northeast Atlantic and the new area of disturbed weather in the southern Caribbean Sea is at this link.
Should be the end of the 2020 Atlantic Hurricane Season officially, but this year mother nature does not care about that.
https://www.aoml.noaa.gov/phod/regsatprod/enso/sst_map_12.gif
India Meteorological Department
Tropical Cyclone Advisory #2 – 8:30 AM IST November 30 2020
DEPRESSION BOB05-2020
==============================================
Pre-Cyclone Watch for southern Tamil Nadu and southern Kerala coasts
At 3:00 AM UTC, The Depression moved west northwestwards during past 3 hours and lays centered over southeastern Bay of Bengal near 7.7N 87.7E, about 710 km east southeast of Trincomalee (Sri Lanka) and 1120 km east southeast of Kanyakumari (India). It is very likely to intensify further into a deep depression during next 12 hours and into a cyclonic storm during subsequent 24 hours.
It is very likely to move west northwestwards and cross Sri Lanka coast between latitude 7.5N and 9.0N during evening/night of December 2nd. It is very like to move nearly westwards thereafter and emerge into Comorin area on morning of December 3rd.
India Meteorological Department
Tropical Cyclone Advisory #1 – 5:30 AM IST November 30 2020
DEPRESSION BOB05-2020
==============================================
At 0:00 AM UTC, Latest satellite and Ship observations indicate that the well marked low pressure area over southeast Bay of Bengal & neighborhood concentrated into a Depression and lay centered near 7.5N 88.0E, about 750 km east southeast of Trincomalee (Sri Lanka) and 1150 km east-southeast of Kanyakumari (India). It is very likely to intensify further into a deep depression during next 24 hours. It is also likely to intensify further into a cyclonic storm. It is very likely to move west northwestwards and cross Sri Lanka coast between latitude 7.5N and 9.0N around evening of December 2nd.
It is very like to move nearly westwards thereafter and emerge into Comorin area on morning of December 3rd.
Forecast and Intensity
============================
12 HRS: 7.7N 87.0E – 30 knots (Deep Depression)
24 HRS: 7.9N 86.1E – 35 knots (Cyclonic Storm)
48 HRS: 8.3N 83.1E – 40 knots (Cyclonic Storm)
72 HRS: 8.5N 80.2E – 35 knots (Cyclonic Storm)
Satellite based intensity is T1.5. Broken low and medium clouds with embedded intense to very intense convection lay over southeastern Bay of Bengal between 6.0N to 10.5N and 83.0E to 90.5E in association with the system. Minimum cloud top temperature is -85C.
3 minute sustained winds near the center is 20 knots with gusts of 30 knots. State of the sea is rough to very rough around the center. The estimated central pressure of the depression is 1003 hPa.
Wrote a blog on the weather coming thru the east, 90L and Lewotolo erupting.. http://skyeponyweather.weebly.com/skyepony-weather/weather-moves-thru-the-east-90l-meanders-and-lewotolo-erupts
https://uploads.disquscdn.com/images/aa798d3ecd02dac1241015ad0a382af2935c5a9a5befe7fe6c946144720ba3a9.png?w=600&h=417
Just competed my 194th update on the 2020 Atlantic Hurricane season at my infohurricanes site (that’s infohurricanes followed by “.com”). Info on 90L and possible southern Caribbean development in the coming days
https://uploads.disquscdn.com/images/7a6e0c4dd34de44a1eec4a2c037355b57300987180b4e970f62c5ace2f397e4b.png?w=600&h=412
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1200 AM CST Sun Nov 29 2020 Valid 291200Z - 301200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND EASTERN GULF COAST REGION...AND THE SOUTHEASTERN U.S. ATLANTIC COAST... ...SUMMARY... Isolated strong to severe thunderstorms remain possible today and tonight across southern portions of the Gulf Coast states into the eastern Carolinas. A couple of tornadoes, and a few locally damaging wind gusts, are the main threats. ...Synopsis... An upper low initially over Oklahoma is forecast to move eastward to the mid/lower Mississippi Valley through the first half of the period, but will gradually become absorbed by a northern-stream trough digging east-southeastward out of the northern Plains/upper Mississippi Valley into the Midwest/middle Mississippi Valley overnight. At the surface, a weak low is forecast to move across the northern Gulf of Mexico near the Louisiana coast toward Mobile Bay during the day, along a pre-existing baroclinic zone. Thereafter, the low is progged to turn northeastward and move quickly northward along the Appalachians, deepening rapidly as it reaches the West Virginia vicinity by the end of the period/Monday morning. ...Central and eastern Gulf Coast/southeastern Atlantic coast... Widespread precipitation is forecast to be ongoing at the start of the period ahead of the advancing upper low, from southern and eastern Texas across Arkansas and Louisiana into southern Mississippi and vicinity. The substantial precipitation and cloud cover -- that should persist through the day -- over the central Gulf Coast states/mid South should maintain a stable boundary layer. Any potential for surface-based convection appears likely to remain confined to southeast Louisiana, southeast Mississippi, and into southern Alabama and the Florida Panhandle through the daylight hours. A separate area of storms may evolve during the afternoon across eastern South Carolina and into the southern Atlantic, near a developing warm front. During the evening and overnight, as the surface low deepens/shifts rapidly north-northeastward, surface-based convection will spread eastward across southeastern Alabama and roughly the southern half of Georgia, and northern portions of the Florida Peninsula ahead of the strengthening cold front. Meanwhile, surface-based convection will shift northward across the eastern Carolinas and eventually into southeastern Virginia, east of the surface low as the warm front shifts northward. Instability is forecast to remain quite limited inland, with generally less than 300 to 500 J/kg mixed-layer CAPE expected. However, increasingly strong and veering flow with height will evolve with time, in tandem with surface cyclogenesis, yielding shear profiles sufficient for supercells. While modest CAPE should remain a limiting factor, a couple of tornadoes will be possible, within a broad SLGT risk area from southern Mississippi east to northern Florida, and north across the eastern Carolinas to southeast Virginia. A few stronger storms may also produce gusty/locally damaging winds, particularly if small bowing segments can evolve locally. Risk will taper off from west to east along the Gulf Coast through the evening, but may linger through the end of the period across portions of Florida, and particularly along the Atlantic Coastal portion of the outlook. ..Goss/Moore.. 11/29/2020India Meteorological Department
Tropical Cyclone Outlook – 8:30 AM IST November 29 2020
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Yesterdays low pressure area now lays as a well marked low pressure area over southeastern Bay of Bengal & adjoining areas of southern Andaman sea and Equatorial Indian ocean.
It is very likely to concentrate into a depression during next 36 hours and likely to intensify further thereafter. It is likely to move west northwestwards and reach near southern Tamil Nadu coast around December 2nd.
Just finished another update on the Atlantic tropics at this link. 99L has bit the dust at won’t develop, but 90L to dive south toward the Canary Islands has a decent shot at developing into a subtropical cyclone. Meanwhile watching for two more possible AOIs as we move into December (one in the southern Caribbean, and yet another in the open central Atlantic).
India Meteorological Department
Tropical Cyclone Outlook – 8:30 AM IST November 28 2020
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A low pressure area has formed over southern Andaman sea and adjoining areas of southeastern Bay of Bengal and Equatorial Indian ocean.
It is very likely to concentrate into a depression during next 48 hours and likely to intensify further thereafter. It is likely to move nearly westwards and reach southern Tamil Nadu coast around December 2nd.
The low pressure area (mentioned above) over Bay of Bengal after moving across Sri Lanka and extreme southern peninsular India is likely to emerge into southeastern Arabian sea around December 3rd.
Good evening to you all,
My latest birdseye view post and chart on the Atlantic tropics, highlighting the two AOIs that remain in the NHC tropical weather outlook, is at this link. In addition I discuss two more possible AOIs that could pop up unbelievably in early December. Looks like the 2020 Atlantic Hurricane Season does not care that the official end of the season is usually November 30.
Sub-trop Kappa near Bermuda and Lambda near Costa Rica? After all these years, knowing the Greek Alphabet finally pays off.
Good thanksgiving evening to you all, just posted my latest birdseye view chart and post of the Atlantic tropics after eating some turkey, viewable at this link.
This is my intro statement to that post, says how I feel about the latest round of activity (99L and AOI in the NE Atlantic) in the tropics: “Although today is the Thanksgiving holiday for many…the Atlantic tropics refuse to go on vacation.”
Could we get a sub-tropical Kappa near Bermuda this week?
Should stay east of Bermuda thankfully.
https://uploads.disquscdn.com/images/f661280c3defb0d7aa87f87f91d6969572b61b1ad52ee9d63906ceb41da5d8b6.png?w=600&h=408
99L
Tropical Cyclone Warning Center Perth
Tropical Cyclone Outlook – 2:00 PM WST November 26 2020
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Tropical Low (01U) is currently located near 10.0S 91.0E, in the far northwest of the region. This low is forecast to move south through till Sunday before moving west and out of the region. There is a low risk of 01U intensifying into a tropical cyclone on Saturday and Sunday, prior to moving west of 90E and out of the region.
The low is not expected to have any direct impact on the Cocos Islands, however rainfall and thunderstorms are more likely while it lies in the northwest of the region, with this activity likely to be in a significantly easing or even clearing trend by Tuesday.
India Meteorological Department
Tropical Cyclone Advisory #24 – 8:30 AM IST November 26 2020
CYCLONIC STORM NIVAR (BOB04-2020)
==============================================
At 3:00 AM UTC, The cyclonic storm “NIVAR” moved northwestwards with a speed of 13 km/h during past six hours and lay centered over north coastal Tamil Nadu near 12.6N 79.4E, about 85 km north northwest of Puducherry and about 95 km west southwest of Chennai.
Cyclonic Storm “NIVAR‟ would continue to move northwestwards and weaken further into a deep depression during next 6 hours and into a depression by subsequent 6 hours.
3 minute sustained winds near the center is 40 knots with gusts of 50 knots. Estimated central pressure of the severe cyclonic storm is 994 hPa.
India Meteorological Department
Tropical Cyclone Advisory #23 – 5:30 AM IST November 26 2020
SEVERE CYCLONIC STORM NIVAR (BOB04-2020)
==============================================
At 0:00 AM UTC, The severe cyclonic storm “NIVAR” moved nearly northwestwards with a speed of 11 km/h during past six hours and lay centered over north coastal Tamil Nadu near 12.4N 79.6E, about 50 km north northwest of Puducherry.
“NIVAR” would continue to move northwestwards and weaken further into a cyclonic storm during next 3 hours.
Forecast and Intensity
=========================
12 HRS: 13.2N 78.8E – 30 knots (Deep Depression)
24 HRS: 14.0N 78.0E – Low Pressure Area
Storm Surge Warning
——————–
Tidal wave of about 0.5-1 m height above the astronomical tide is very likely to inundate the low lying areas of north coastal districts of Tamil Nadu (Villupuram and Chengalpattu districts) during next 03 hours.
As per satellite imagery, broken low and medium clouds with embedded intense to very intense convection lay over southwestern and adjoining west central Bay of Bengal, between 11.0N & 12.5N and 78.0E & 80.5E in association with the system. Minimum cloud top temperature is -93.0C.
3 minute sustained winds near the center is 50 knots with gusts of 60 knots. Estimated central pressure of the severe cyclonic storm is 982 hPa.