Intelligence reports and country risk assessment by Strategic Intelligence Service draw out scenarios/biases characterizing a prelude to terror attacks.
This terrorism risk assessment covers a period between April and June 2016, as such attacks are highly likely during that period. This is factored by the rainy season. Terror cells easily use heavy rain at night as camouflage to move weapons to be used in attacks to safe houses near the target areas
Elementary indicators include
Warnings by HSM (Harakat Al-Shabaab Mujahideen) that they'll conduct attacks
General alertness in Kenya (terror advisory by state security agencies)
Increased activity of jihadist cells in Tanzania and Kenya
Countries likely to be attacked include Tanzania and Kenya
Tanzania has not experienced large scale attacks. However, a bulk of Al-Shabaab foreign fighters is from the country. There are so far over 1000 profiled sympathizers and radical followers of the terror group based in Tanzania. Most of these suspects are using communication networks to get conscripted into the group. This shows Al-Shabaab may have a very versatile Tanzania based affiliate. Al-Muhajiroun affiliate of the HSM has facilitated this online recruitment.
Kenya's success in Somalia remains very commendable. This makes the country prone to terror attacks. The terror group views Nairobi as one of its greatest enemies. Kenya continues to decimate Al-Shabaab's capabilities (military & ideologically) thus weaken the group significantly.
Uganda which has troops in Somalia has also been a target. UPDF AMISOM contingent is based in Mogadishu and its neighboring districts thus viewed by HSM as an enemy.