All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ʻalayhi wa sallam, is His slave and Messenger.
According to the majority of the scholars, washing the hands thrice is recommended (not obligatory) upon waking up from the night's sleep. The Hanbalis held that it is obligatory on the person who wakes up after a night's sleep that invalidates ablution. They maintained that it is an independent obligation aside from the recommended act of washing the hands at the beginning of ablution. Some scholars held that the two acts overlap and that it is sufficient to wash the hands thrice. The Hanbali scholar Al-Buhooti said:
“It is obligatory to wash the hands thrice with the intention of performing that act of worship and reciting the Basmalah (saying: Bismillah [In the name of Allah]) when waking up from a night's sleep that invalidates ablution. Ibn Qaasim said, ‘It is required of him to wash his hands thrice upon waking up and thrice again as an act of Sunnah at the beginning of ablution given the apparent indication of the hadith.’ [Al-Haashiyah] A number of scholars held that it is possible that when a person washes his hands and then performs ablution immediately with no interval between them, the objective is accomplished and this is sufficient (he does not need to wash his hands again at the beginning of ablution). The Companions who related the manner in which the Prophet, sallallahu ʻalayhi wa sallam, used to perform ablution did not mention that he washed his hands again after the first time he washed them (when he woke up).” [Ar-Rawdh Al-Murbi’]
As for blowing the nose thrice upon waking up, it was commanded by the Prophet, sallallahu ʻalayhi wa sallam, without restrictions in the hadith narrated on the authority of Abu Hurayrah, may Allah be pleased with him, and cited in Saheeh Muslim. However, another version of this hadith restricted this command to ablution (i.e. if the person wants to perform ablution after waking up). This is why many scholars relied on the report that indicates restriction to interpret the one with the unrestricted command. They thus held that blowing the nose thrice is required when a person is performing ablution only.
Shaykh Saalih Al-Fawzaan, may Allah have protect him, said:
“Blowing the nose thrice upon waking up from a night's sleep: some scholars held that it is obligatory while others held that it is recommended. The correct view is that it is obligatory because the apparent indication of the command (in the relevant hadith) is the obligation. The question arises as to whether the person should blow his nose upon waking up even if he is not performing ablution. The apparent indication of the hadith is that it applies to everyone who wakes up from sleep, even if he is not performing ablution. However, the version of the hadith in Saheeh Al-Bukhaari restricts this general indication; it reads, ‘When one of you wakes up and wants to perform ablution, let him blow his nose thrice.’ Hence, the restricted version is relied upon when interpreting the general one; meaning that when a person wakes up from sleep and wants to perform ablution, he should blow his nose.”
It should be noted that the scholars held different opinions regarding the ruling on sniffing water (Istinshaaq) and blowing it out (Istinthaar). The Hanbalis held that they are obligatory, while the majority of scholars held that they are recommended. There is no doubt that it is more prudent to do them.
Allah knows best.