According to the weather forecast for February 19, the sea surface temperature in the central Pacific region continues to warm up, while seasonal atmospheric signals such as Madden-Julian (MJO) fluctuations begin to become clear again after a period of turbulence.
The weekly average index of ENSO is currently at -0.130 degrees C, exactly the neutral threshold. Compared to before, this level increased by 0.236 degrees C, equivalent to an increase of 64.48%. Meanwhile, the 3-month average reached -0.650 degrees C, still within the weak La Nina threshold but has increased by 0.056 degrees C (an increase of 7.98%). This shows that the warming trend is taking place relatively clearly.
Forecast models, especially the CFS. v2 combination, lean towards the possibility that ENSO moves to neutral status in March 2026 (after the Lunar New Year in Vietnam) and remains at least until July-July 2026.
The probability of transitioning from La Nina to neutral in April-April 2026 is about 60%, and the probability of maintaining neutral in the Northern Hemisphere summer is about 56%.
MJO activity is becoming clearer. Since mid-February, the resonance interaction between the Rossby wave and the remaining MJO signal in the Indian Ocean has made the convection structure clearer.
Unusual easterly winds spread westward through the Indian Ocean in the first half of February, while strong west winds appeared in the east of the International Day Trading Line and gradually weakened in the East Pacific. Southern equatorial monsoon winds near the Day Trading Line remain strong.
Two large model systems, GEFS and ECMWF, both predict that the MJO signal tends to spread eastward in the near future, but there are still differences in intensity and phase velocity.
GEFS generally gave a stronger and faster scenario, even some members predicted a strong event in the Pacific in early March. Meanwhile, most ECMWFs predicted weaker performance but still maintained the MJO structure.
According to overall assessment, MJO may play a role in shaping the global tropical convection model in the short term, although the amplitude is still uncertain.
This activity could increase the possibility of tropical storms/cyclones forming near Western Australia in the coming weeks.
Regarding the Tet weather forecast in Vietnam, according to the National Center for Hydro-Meteorological Forecasting, on February 19, cold air has affected some places in the Northwest and Central Central regions, causing rain and scattered light rain; the temperature dropped by 4-6 degrees Celsius.
From the night of February 18 to February 19 (the 2nd day of Tet to the 3rd day of Tet), the Northern region and Thanh Hoa (except Lai Chau, Dien Bien) have the lowest temperature of 16-19 degrees C, the Northern mountainous region has places below 13 degrees C; average temperature 18-20 degrees C, the Northern mountainous region has places below 15 degrees C.
Hanoi weather forecast for February 19th (3rd day of Tet): Some places with rain. Cold weather. Highest temperature 20-23 degrees C, lowest 17-19 degrees C.
From February 20-22 (the 4th to the 6th day of Tet), Hanoi will have light rain in some places, morning fog and light fog scattered. Cold at night and morning. Highest temperature 23-26 degrees C, lowest 19-21 degrees C.
Southern region from February 19-22 (the 3rd to the 6th day of Tet): Few rains, sunny days, hot sun in the East. Highest temperature 32-35 degrees C, in the East some places above 35 degrees C. Lowest temperature 23-26 degrees C.
