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Which #Kenyan Counties will be the first to face the El Nino wrath? Reports of moderate-to-heavy rains have been confirmed along the Kenyan Coastal strip & Southern Somalia as predicted last month. Consolidated multi-model precipitation charts, which tell us the probability of rainfall exceeding the long term mean, show an intense wet spell in Southern Somalia, the #Kenyan Coastal strip & Northern Coast of Tz. This wet spell is expected to run for the next 10 days or so. Mombasa, Kwale, Kilifi, Tana Delta & Lamu will be the first counties to get a taste of the Strong El Nino & +ve IOD rains. The CFS-V2 model shows next in line are North Eastern Kenya Counties of Mandera (high risk of serious flooding in early October), Wajir & Marsabit. The third batch will be Eastern counties of Isiolo, Meru, Embu, Tharaka Nithi, Kitui, Garissa, Tana River and Taita Taveta some time from mid-October. It's worth noting that the El Nino rains enhancement will come in an East-West wave. The dates in these charts should not be confused with the rainy season onset dates. Those will be updated separately.

Mombasa may have received rainfall exceeding 100mm in the last 72 Hrs

Where are we likely to see heavy afternoon thunderstorms, intense cloud burst & probably hailstorms today in #Kenya? Watch:

Long video clip alert: Sunshine Hours I'm getting so many queries about the sudden cloudiness & cool/chilly weather in #Nairobi & it's environs. This kind of cold is not the usual July/August kind of cold. You can tell even by the cloud type. Now, back-to-back cold fronts, some as wide as 10,000KM, are pulling Northward from the Antarctic Polar region into the Sub-tropical Atlantic/Indian Oceans & South Africa. Strong south easterly winds that are blowing directly onshore the East African Coast are actively interacting with these fronts in the Southern Indian Ocean, bringing an unseasonal cooling & cloudiness to our region this week. Sunshine Hours & temperatures will drop further tomorrow, Thursday & Friday before getting warmer over the weekend in the #Nairobi Metro area, Ukambani & the Coast. Watch:

"Potential weather shocks". As usual, the shocks will find us unprepared.

Long clip alert: This week, increased cloudiness due to the recent Madden Julian Oscillation wave across Equatorial Africa & the Indian Ocean will reinforce chilly/cool weather over the highlands East/West of the Rift including #Nairobi Metro Area & parts of South Eastern Counties. Today & tomorrow may be particularly chilly in some places, with very few sunshine hours as shown in the clip. However, Wednesday may be warm, then the cold resumes on Thursday & Friday. It may be warmer on Saturday but chilly on Sunday. Watch: 👇

This week, influx of cold air from the south reduces significantly. Outgoing Longwave Radiation (OLR) anomaly predictions indicate reduced overall cloudiness in the #Kenyan highlands inclusing the #Nairobi Metro area. Consequently, we shall see a significant uptick in the average daily temps with highs of 26C to 27C in Nairobi on some days. Tomorrow Tuesday & Thursday may feel quite warm. Slight cooling highly likely over the weekend. Forecast predictability at 80%-90% due to the settled weather we're currently experiencing in the city. Watch:

Huko North Rift mtaifeel proper hadi Sept. It's supposed o be raining but it's not raining as usual. Temperature anomalies forecasts are up to +3 degrees celcious.

Long range multi-model climate ensembles are pointing to two things in the coming months for #Kenya : 1. A not-so-good JJA rainy season for North Rift, Central Rift and Western (this has been mentioned in my previous analyses) 2. Enhanced precipitation from as early as August onwards (surprising) for North Eastern, Eastern and the Coast The emerging Super El Nino and lower than normal Atlantic Ocean SSTs are likely to shake up the local weather and climate in a big way. May 2026 model run outcome updates coming soon.

As a potentially strong El Nino pattern emerges in the tropical Pacific, long range multi-model ensembles persistently paint a picture of suppressed rains in much of Kenya's Rift Valley, Western & even Nyanza in the Jun-Jul-Aug season. The Ethiopian highlands, Northern Uganda, South Sudan, Sahel region & even much of the Indian sub-continent will witness negative rainfall anomalies throughout the monsoon season between June & Sept 2026. Weaker monsoon winds in the Indian Ocean & increased vertical shear in the Atlantic all driven by the emerging El Nino will force these conditions over the said regions

Longer sunshine hours and warmer-than-usual temepratures expected in Nairobi & much of the Kenyan highlands in the coming days. Reference time 0006Hrs when the lowest daytime temps are normally recorded Watch:

Updated Seasonal Outlook for #Nairobi #Kenya : The JJA cool/cold season feels much warmer this year, with some days max temps daytime hitting 28C in #Nairobi . Two major factors are at play here: The Southern Annular Mode (SAM) & the Madden Julian Oscillation (MJO). SAM is the climatological pattern that determines far into the sub-tropics the frigid Antarctic Polar air mass spreads & the strength of the cold fronts that hit Southern Africa during Winter. This phenomenon has two phases: +ve & -ve. The -ve phase allows the cold Antarctic airmass to spread further into the sub-tropics, cooling down the Southern sections of the Indian & Atlantic Oceans then trade winds bring the cooling & drizzly effect into East African highlands & plateaus over the JJA season. The +ve phase has the reverse effect. SAM indices have been in a prolonged +ve phase since May 2026. Model data shows that this has been one of the highest +ve indices, causing the Antarctic polar air mass to stay constricted around the South Pole. This has reduced the frequency of cold fronts hitting Southern Africa & even less reports of snow in countries like Lesotho & warmer temp anomalies in much of East Africa. It's worth noting that the current strong El Nino event in the Pacific has strengthened Westerly winds around the South Pole, leading to the strong +ve SAM index. On the other hand, the MJO outgoing longwave radiation has been quite active in the Western Pacific & Western Hemisphere since late May up to now, with very weak & brief signals over Equatorial Africa & the Indian Ocean. Consequantly, strong westerlies over the West Pacific have starengthened the developing El Nino to near-record strengths at this time of the year. Also, very strong tropical storms/typhoons have been reported in the West Pacific over recent weeks. At the same time, much of equatorial Africa, including #Kenya & the Indian Ocean experience less cloudiness, low relative humidity & reduced atmospheric convection. Looking forward into the 2nd half of July, Aug & early Sept Nairobi will experience settled, dry and warmer than usual conditions. Off-season rains will get scarcer and the city will get sunnier & dusty. After the Sept equinox, the tables turn & a very rainy ONDJ season will be upon the city courtesy of El Nino, +ve IOD (may emerge any time from Aug, per NMME model family) & probably a -ve SAM index.

In the next few days, upper level (200mb winds) sub-tropical & the Antarctic polar jet-streams will expand further into the African hinterland. The sub-tropical jet-stream will pull up as far northwards as Southern #Tanzania , while the Polar jet-stream may touch the Southern tip of South Africa. These wind-band movements will bring a blast of cold air into Southern and Eastern Africa especially over the weekend & early next week, leading to cool/chilly weather especially in the #Kenyan highlands & South Eastern Counties.

#Nairobi weather is blowing hot and cold lately. Kunani? We'll be reviewing the seasonal climate outlook for Nairobi in the coming days and start tracking the evolution of the city's weather conditions all the way to the Sept equinox after which we expect heavy rains powered by El Nino and probably, a positive IOD. Stay tuned!

A side-by-side comparsion of the multi-model super-ensemble seasonal projections for Nov 2025 & Nov 2026. F1 projection as at 20/06/2025; F2 as at 20/06/2026. Last year at a time like now, a moderate La Nina was developing in the Equatorial Pacific, while a negative IOD was anticipated in the Equatorial Indian Ocean. These a combinantion of these two phenomena seriously suppressed OND seasonal rains in much of the Horn of Africa resulting in devastating drought. Fast forward to June 2026: El-Nino conditions are present in the Equatorial Pacific, and, per model projections, the event is expected to strengthen into a Super El Nino by November 2026 probably breaking previous records. Sea surface temperature anomalies in Nino 1+2, Nino 3, Nino 3.4 & Nino 4 regions of the Pacific have already reached El Nino thresholds & are rising as the days pass. A positive phase of the IOD is expected to get established in the Indian Ocean in August, bringing large volumes of warm waters to the sea off the east coast of Africa. A coincidence of a Super El-nino & a strong positive IOD is likely to power record-breaking rainfall performance across the Horn of Africa including #Kenya in OND rainy season this year. North Eastern, Eastern, parts of Central & the Coast are likely to witness an early start of seasonal rains some time in September, if these projections verify. Between now & then, the teleconnections will continue to suppress rains in the Rift, Western, Nyanza & parts of Central.

The Madden Julian Oscillation (MJO) has been lingering in the Western Pacific Ocean & Western Hemisphere for a couple of weeks, triggering Westerly Wind Bursts that have created massive Kelvin waves, helping in the establishment of El Nino. Per the Euro & BOM models, from this weekend, a low amplitude MJO pulse enters phases 1, 2 & 3 bringing higher relative humidity, moist westerly winds & improved atmospheric convection over the Kenyan Rift Valley, Central & Western. Showers are already falling in some places in these regions and heavier rainfall is expected in the last 10 days of June (from Monday next week), ending weeks of a dry spell that has caused widespread crop failure.

And... It turned out to be a hailstorm! Pics shot in Kipipiri Sub-County, Nyandarua this evening. Photos: Courtesy

Starting July 2026, @YearToDateLLC will take weather and climate model analytics a notch higher with more regular and detailed analyses/reanalyses of short range and long range forecasts. We will be closely tracking model updates for insights on the evolution of the super El Nino event and it's likely impacts on the weather in Sub-Saharan countries especially Eastern, Central & Southern Africa, in the coming months. Keep on following!

"Hey Maithya. Why is it so cold & cloudy in #Nairobi na hakuna mvua?" Well, a quick check across the models shows that today's peak daytime temps in #Nairobi at 3PM won't cross 22 degree Celcious, due to dense cloud cover. An examination of wind patterns shows a cool stream of dry lower atmospheric continental winds from a cooler Southern Africa region blowing into Kenya through #Mozambique & #Tanzania. This jet of cool air won't be sustained for long and warm weather will resume in much of KE in the coming days. The persistent cold season in Kenya is expected to start from mid to late June, after the Southern hemisphere winter solstice.